<p>The post of @Mmmmmm about traffic reminded me of <a href="https://en.wikipedia.org/wiki/Braess%27s_paradox" rel="noreferrer">Braess's Paradoxon</a>: There are situations in a traffic network (under the assumption that all drivers are rational) where <em>removing</em> some roads leads to a lower average amount of time spent driving.</p>

<p>While the paradox itself was constructed with another goal in mind it assumes that all drivers know the optimal path to take.</p>

CC BY-SA 4.0
2020-02-26T12:34:47.233Z
Note that you can also adapt this example to the question: The road does not have to be removed in reality but only from the knowledge of all drivers.
Wrzlprmft
CC BY-SA 4.0
2020-02-25T12:49:39.463Z
2020-02-25T12:49:39.463Z
flawr
<p><a href="https://www.nytimes.com/2020/02/20/opinion/warren-bloomberg-debate.html" rel="nofollow noreferrer">Paul Krugman</a> recently discussed the <a href="https://en.wikipedia.org/wiki/Bloomberg_Terminal" rel="nofollow noreferrer">Bloomberg terminal</a>, a classic example of a resource with the following properties:</p>
<ol>
<li>Those who get it are at an advantage, so naturally everyone gets it;</li>
<li>It's not free, so everyone getting it cancels out the benefits, making everyone worse off.</li>
</ol>
<p>The world must be full of examples of this. Dave Gorman once mentioned another example, where everyone on his flight, him included, had paid for priority boarding. You can guess what happened.</p>

CC BY-SA 4.0
2020-02-26T08:46:36.323Z
Looks like a classical public goods game, but I don't think it qualifies as an example where providing all agents with more information makes everybody worse off. The extra information has to be purchased here and is not simply provided to everyone (for free). If it were, then everybody would end up as well off as before (assuming that you profit only from an informational advantage over others).
VARulle
CC BY-SA 4.0
2020-02-26T16:34:24.970Z
Another classic example: health insurance.
StackOverthrow
CC BY-SA 4.0
2020-02-27T14:12:35.717Z
@user560822 There's nothing wrong with health insurance in general - it's a service that allows you to trade risks and large sudden sums of money for regular payments. It's no different from taking a loan, for example. What you're thinking of is the "bonuses" health insurance companies try to give their customers to choose their particular company, and which are the main reason the US health system is such a mess - e.g. having doctors increase base-line prices, just so the insurance company can give "discounts" for their customers even though they're just paying the market price.
Luaan
CC BY-SA 4.0
2020-02-27T14:15:38.487Z
The thing is, if people stop doing that, it will become advantageous again - which balances out the information value. If enough people learn there's no point in having priority boarding, it will become useful again :) This is just an example of sub-optimal Nash equilibrium - everyone would be better off if noone did it, but every individual will be at a loss for being the one not to do it. Heck, it's well known in evolutionary biology - trees only benefit from growing so tall because other trees are tall; all trees would be better off shorter, but can't afford to be.
Luaan
CC BY-SA 4.0
2020-02-27T16:02:48.523Z
Arguably, Bloomberg terminals are an example for *withholding* information (and then releasing it only for a fee), so it could actually be a counter-example. If everybody had perfect market information the market would be closer to perfect; optimal markets again lead to optimal resource allocation which improves overall welfare.
Peter - Reinstate Monica
CC BY-SA 4.0
2020-02-27T19:03:35.780Z
@Luaan Health insurance removes the incentive for care providers to compete on price and replaces it with a perverse incentive to charge the maximum allowed. This drives up prices until nobody can afford health care without insurance, so everyone wants insurance, to everyone's detriment. There is no "market price" for health care as long as insurance is legal. It's a perfect example of what this answer is about.
StackOverthrow
CC BY-SA 4.0
2020-02-28T07:44:12.173Z
@user560822 No, it doesn't. And it didn't for a quite a while even in the US. Insurance companies put pressure on health care providers to lower their prices (and avoid unnecessary _covered_ diagnostics/treatment etc.). Of course, it's a layer of indirection, and that has costs. Add that many companies started paying the health insurance of their employees as a benefit, and you have _another_ layer of indirection. The absurdity in the US system is that, as you correctly pointed out, the health care prices aren't market prices - they're a signalling cheat saying "insurance is cheaper!"
Luaan
CC BY-SA 4.0
2020-02-28T16:38:13.957Z
@Luaan The insurance company pressures for lower prices to increase their own profits. A functional market would force prices *at least* as low, and probably much lower, because consumers would have vastly more freedom of choice. Insurance is intentionally designed to limit consumer freedom as well as consumer knowledge.
StackOverthrow
CC BY-SA 4.0
2020-02-25T17:48:52.860Z
2022-10-15T06:39:11.407Z
2022-10-15T06:39:11.407Z
J.G.
<p>The “to be announced” or TBA market for agency mortgage-backed securities is a great example of this. </p>

<p>The short version is as follows: The TBA market is a market wherein one can purchase or sell for future delivery pools of mortgages that conform to certain characteristics (e.g., and to vastly simplify, 30 year mortgages at a 4.5% coupon) without specifying the particular mortgages to be delivered. Only government- or agency-guaranteed mortgages are eligible for TBA delivery. Of course, the incentive is for the pool seller to deliver the worst mortgages possible, but “worst” is entirely based on the mortgages’ prepayment characteristics, not on their credit quality (as they’re all guaranteed).</p>

<p>Why is this good? It makes for a really liquid market, because everyone just prices everything assuming it is bad. Buyers don’t waste a bunch of time trying to analyze pools trying to uncover some marginal advantage, because that’s simply not an option. So they can buy securities in this market blindly, knowing that they’re only being shortchanged in the selection of mortgages in the pools they buy to a predictable degree that is already priced into the market. This is really useful given that most of the buy side doesn’t have a ton of resources to spend on pool-level evaluations. </p>

<p>The result: a multi-trillion dollar market in annual primary volume (not counting financing that occurs in this market), that is estimated to be responsible for reducing the cost of mortgage financing in the US by <a href="https://www.newyorkfed.org/medialibrary/media/research/epr/2013/1212vick.pdf" rel="noreferrer">10-25bps on average</a>.</p>

CC BY-SA 4.0
2020-02-25T11:57:51.087Z
So basically, everyone having *less* information makes everyone *better* off?
Criticize SE actions means ban
CC BY-SA 4.0
2020-02-25T12:59:10.407Z
Yes, which also means that if they had *more* information, they would be *worse* off (which is true for non-TBA-eligible securities).
dismalscience
CC BY-SA 4.0
2020-02-27T14:08:53.137Z
Except it only _looks_ like you're better off, because _somebody else is paying the bill_. The guarantee simply makes the information _irrelevant_ - it overrides the _reasons_ why the information is (normally) useful; instead of you being responsible for the quality of your investment, if you make a mistake, the taxpayers pay for it - essentially, you're handing everyone's money to pay for the past times/investments of a part of the population.
Luaan
CC BY-SA 4.0
2020-02-27T14:20:03.610Z
@Luaan You’ve clearly not read the linked paper or any of the relevant literature on this topic. The estimated liquidity benefit is comparing guaranteed TBA-eligible securities to *also guaranteed* non-TBA eligible securities. What is being valued is *not the guarantee at all*.
dismalscience
CC BY-SA 4.0
2020-02-27T14:29:24.203Z
No, it just says that if you can have general buy and sell orders, and somebody else guarantees the commodity being bought and sold, you will have a better performing market than if you can't have general buy orders. The liquidity isn't enhanced by the lack of information, it's enhanced because you _get_ the information - how much people are willing to give you for a given commodity, regardless of how good an investment it is. The information "there's 20 people willing to pay me $20 for X" is more valuable than "there's 1 willing to pay $23 for X1, 3 who pay $26 for X2, ..."
Luaan
CC BY-SA 4.0
2020-02-27T14:40:31.717Z
@Luaan You’re correct that the liquidity comes in part from less specificity in orders but you are missing something important: the guarantee itself does not make the underlying securities the same. They still differ significantly in their interest rate characteristics and thus their underlying value. The TBA cheapest-to-deliver feature is *also* destroying information, in addition to the guarantee. I ask that you please read the reference provided. I’m happy to provide more.
dismalscience
CC BY-SA 4.0
2020-02-25T03:09:06.983Z
2020-02-25T03:09:06.983Z
dismalscience
<p>This sounds glib, but The Internet is an ongoing example.  </p>

<p>In economic models where access to information is an explicit factor, we often gloss over the fact that mere exposure to information about the state of the world is not enough to improve welfare - one also needs the cognitive skills to use those facts to develop plans in support of preferences, and also the abilities necessary to manipulate the environment in execution of those plans.  <em>Homo economicus</em> is implicitly assumed to possess both, but this is manifestly untrue about <em>Homo sapiens</em>.  "The Death of Expertise" by Tom Nichols is a good first-look at the scope of the problem, viewing the interplay between limited human capacities and unfettered access to information ("signals", really) through a sociological lens.  The Dunning-Kruger effect and the competition between identity/belonging goals and accuracy goals are two key elements to this. </p>

<p>If you want to get deeper into it, a host of other empirically-supported cognitive biases  - anchoring, affect heuristic, availability bias, and so-on - suggest that the phenomenon of acting in response to an information set that becomes more complete with time exhibits hysteresis.  This is tremendously problematic when recognizing that while <em>Homo economicus</em> is presumed to hold all of the available information in her head in one simultanous pre- <span class="math-container">$t = 0$</span> moment, each of the information sets held by every <em>Homo sapiens</em> carries a slightly different history than any other.  To the extent that these information sets are compiled by experiencing signals available on the Internet, <em>a proiri</em> one should expect that a bigger pool of signals will yield a wider variation in the histories, and less rather than more concensus about the state of the world and which actions (usually requiring the solution of co-ordination problems) might lead to greater social welfare.</p>

CC BY-SA 4.0
2020-02-27T14:04:37.793Z
Is this fair, though? Of course _wrong_ information, or information that is improperly interpreted can be bad for you, but that's not exactly a paradox, is it? If I lie to you to make you send me a million dollars, it's not a problem of having too much information, but rather too little :) Indeed, a common way of manipulating people is to tell the truth, but at the same time withhold critical information that puts the truth in context etc. We're dealing with probabilities here - is there correct, well interpreted information that _on average_ gives you worse outcomes than not knowing?
Luaan
CC BY-SA 4.0
2020-02-27T17:18:17.910Z
Well this is why I prefer to use the term "signal" rather than "information".  It is also why I include the importance of *having the skill to act*.  Without that, even true signals can lead to sub-optimal outcomes.  And finally, it seems like you're still clinging to the assumption that all pertinent information is available pre-$t = 0$; this simply isn't true.  We receive a stream of signals that evolves throughout time, and so by definition it will always be incomplete - and some of that missing data will be "critical" in the sense you mean it.  There is no real counterfactual to that.
heh
CC BY-SA 4.0
2022-10-18T14:30:09.427Z
Piggybacking off the internet example - any time there are costs to processing the signal, such as agents having limited cognitive load, it is possible to provide "too much information."
RegressForward
CC BY-SA 4.0
2020-02-24T15:43:07.407Z
2020-02-24T15:43:07.407Z
heh
<p>This is a very old idea in general equilibrium models with imperfect information and incomplete markets.
More information could be detrimental if the agents that face uncertainty situations decide to insure and the equilibrium under full insurance is pareto optimal.</p>
<p>If in such a situation the state would be revealed with a perfectly informative signal the state of nature would be known before the opening of the market and so the insurance possibilities for the agents are destroyed.</p>
<p>Take a look at these links:</p>
<ul>
<li><a href="https://www.jstor.org/stable/pdf/1817048.pdf?casa_token=ayB-QLEbbIAAAAAA:P-x4m1r4lv5ateQXs2B91pjHyY7yx8NPPZZu-x1BXzcQlJYknCA8k_Xf0UwokCM-AGit8QM-62_dBGTTp8JJ1jv00xL9cneq7sUWCAH7j2rlVQRrIwNveg" rel="nofollow noreferrer">Hirshleifer (1973)</a></li>
<li><a href="https://books.google.it/books?id=vppTCIGyoK4C&amp;pg=PA301&amp;lpg=PA301&amp;dq=destruction%20of%20insurance%20possibility%20and%20reduced%20welfare&amp;source=bl&amp;ots=ydL-bQ-6ze&amp;sig=ACfU3U0xIEJDiKWAfD9ZGD0rX0V6qE_PFw&amp;hl=en&amp;sa=X&amp;ved=2ahUKEwj7x-_jmu3nAhUVQkEAHTLRABEQ6AEwAnoECAcQAQ#v=onepage&amp;q=destruction%20of%20insurance%20possibility%20and%20reduced%20welfare&amp;f=false" rel="nofollow noreferrer">Information Economics By Urs Birchler, Monika Bütler</a></li>
</ul>
<p>there was also another example in eeckhoudt, gollier and schlesinger &quot;Economic And Financial Decisions Under Risk&quot; but I cannot find it right away.</p>
<p><strong>EDIT</strong>: @Giskard Example:
Think about an example where you have two consumers with concave utility functions and endowments <span class="math-container">$ \omega_1=(1,0) $</span> and <span class="math-container">$\omega_2=(0,1)$</span> and state dependent utilities that assign 0 utils to the consumption of one of the two goods in one of the two states.</p>
<p>With the same utility functions and same endowments the economy is in an edgeworth box and as long as the agents are risk adverse they would like full insurance i.e. they will choose a point on the 45degree line with same consumption in the two states.</p>
<p>However, if a perfect signal reveals the state of nature before the spot market opens the guy that has the &quot;bad&quot; good cannot insure anymore because this economy doesn't satisfy the minimal revenue condition and there would be no trade. Overall, the concavity of the utilities and the decreasing returns of consumption guarantee that the welfare is higher in the case of full insurance than under perfect information.</p>
<p>This could be the case in a very simplified economy where the endowments are two different antivirals and only one virus (state) will attack (realize in) our fantasy world. But I have read also a conceptually very similar example on the insurance market in the book that I cited.</p>
<p><strong>EDIT 2</strong>: Taking back Mas-colell book I have found this:
<a href="https://i.sstatic.net/a7hKD.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/a7hKD.png" alt="enter image description here" /></a>
you could look into Spence (1973) signalling model where even if the signal is not costly could create such a problem!</p>

CC BY-SA 4.0
2020-02-25T20:41:52.803Z
I have read the second book (several years back), but I still do not understand what you mean. Why is it bad that the insurance possibilities are destroyed? If you already know everything, you don't need ex post insurance? And ex ante insurance is not destroyed.
Giskard
CC BY-SA 4.0
2020-02-26T09:38:37.893Z
In your example total welfare might decrease, but the situation with information on the state of nature doesn't seem to be Pareto inferior to the one without information. The agent with the "good" good is not made worse off by revealing the state of nature.
VARulle
CC BY-SA 4.0
2020-02-26T09:49:33.347Z
This comment really surprises me. Total welfare may be in doubt (it will depend from the exact curvature of the utilities), but for sure the certain situation is a pareto deprovement. The "bad" agent has utility of zero so is obviously worse off and it is not a pareto improvement.
KArrow'sBest
CC BY-SA 4.0
2020-02-27T09:07:42.397Z
@KArrow'sBest: Well, for being Pareto inferior compared to the certainty situation both agents would have to be strictly worse off.
VARulle
CC BY-SA 4.0
2020-02-27T10:56:40.947Z
@VARulle, I know the definition. I believe, that also the agent with the "good" good would be worse off if both states at t=0 (before the signal) have p=.5 he will loose half of the time and will end-up with expected utility lower than the case with full insurance.
KArrow'sBest
CC BY-SA 4.0
2020-02-28T09:55:10.167Z
@KArrow'sBest, I don't agree. The agent with the "good" good wins by definition, so he cannot "lose half of the time". Let's normalize $u(0)=0$ and $u(1)=1$. You seem to be comparing ex-ante expected utilities which are $Eu_i=u(1/2)>1/2$ for both without information and $Eu_i=1/2$ for both with information. What I mean with "being made worse off" by being informed is a causal chain, so you have to compare the respective ex-post utilities. But those will be $u_i=1$ and $u_{-i}=0$ with information, which is not Pareto inferior to $u_i=u_{-i}=u(1/2)$ without information.
VARulle
CC BY-SA 4.0
2020-02-28T16:30:20.010Z
@VARulle Thanks for the numeric example, I also had this approach the first time I have seen the example and at a first sight may be correct. However, it is enough to modify the trade to be repeated $n$ times with the same conditions each time, to have the no information case as a pareto improvement of the one with signals, and it is given the concavity of $u()$. I think I have studied this exact example in mas-colell advanced micro, either in chapter 6 or 19.
KArrow'sBest
CC BY-SA 4.0
2020-02-29T13:16:43.847Z
@KArrow'sBest: Yes, you're right, I finally understand what you mean. Nice example, thx!
VARulle
CC BY-SA 4.0
2020-02-25T17:23:29.880Z
2022-10-18T13:43:34.530Z
2022-10-18T13:43:34.530Z
KArrow'sBest
<p>Let me contribute. Excessive and unnecessary innovation in science and technology is an example where better information makes everybody worse off.</p>
<p>Excessive Innovation: smartphones with apps that spoiled our lives. Endless cheap entertainment such as Youtube contents (very cheap, by swiping the phone screen), Instagram contents, etc. Online smartphone games. These free service makes less educated people less intelligent and impatience (instant services provided by smartphones can develop a habit that you expect thing to be done instantly). This does not apply to everyone of course (for example: a highly occupied person may be distracted against using smartphones)</p>
<p>Unnecessary Innovation: the advancement of Artificial Intelligence and open source give power to any person (good or bad). It can be abused by making fake political videos, fake videos to criminalize someone, erotic robots, fake humans (robots).</p>
<p>Atomic bomb is also another example. Which is the result of some information or knowledge on physics.</p>
<p>*Please debate my arguments, I would appreciate it.</p>

CC BY-SA 4.0
2022-10-17T08:19:34.570Z
It can be debated if these are really examples where everybody (!) is made worse off. But even if this is granted, the reason seems to be that individuals are lured into doing things that make them worse off. Rational agents (which I assumed in my question) wouldn't do that.
VARulle
CC BY-SA 4.0
2022-10-16T16:19:04.783Z
2022-10-16T16:19:04.783Z
Redsbefall
<h2>Cases where the information increases perceived value but not real value</h2>

<p>Information that can only be used for harming others and/or self are generally not helping the broad public.<br>
The ongoing <a href="https://www.vox.com/2018/7/31/17634558/3d-printed-guns-trump-cody-wilson-defcad" rel="nofollow noreferrer">efforts to pursue 3D printed guns</a> is one of such topics; while you may argue that some people in certain cases benefit from them, they are generally undesirable as knowledge.<br>
Even more so, public information on nuclear devices can <a href="https://en.wikipedia.org/wiki/David_Hahn" rel="nofollow noreferrer">ruin a person's life</a> while not likely making anyone better off.</p>

CC BY-SA 4.0
2020-02-27T13:54:48.043Z
So basically the fact that everyone is better off when nobody has guns than when everyone has a gun (even though every individual person is better off having a gun), but where the source of the guns is information? Yeah, that works.
Criticize SE actions means ban
CC BY-SA 4.0
2020-02-25T17:00:46.310Z
2020-02-25T17:00:46.310Z
user3819867
<p>Not an exact example but here's a case when omniscience is a disadvantage. </p>

<p>Suppose I'm playing a game of chicken where I'm driving straight at an opponent and whoever swerves first loses. If I know my opponent is omniscience or can read my mind [and doesn't have a death wish], then I can confidently conclude that I need never swerve. My opponent will read my mind and realize that I will never swerve, and hence realize he be the one who has to swerve.</p>

CC BY-SA 4.0
2020-02-24T22:54:23.137Z
In your example, more information does not make *everybody* worse off.
Herr K.
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2020-02-25T01:12:05.947Z
@HerrK. Ok, what if both you *and* your opponent are omniscient?
Andy
CC BY-SA 4.0
2020-02-25T06:16:29.957Z
@Andy: Then one of the Nash equilibria will be played. But I still don't see how that hurts both players.
Herr K.
CC BY-SA 4.0
2020-02-24T22:04:56.150Z
2020-02-24T22:04:56.150Z
Keith Vetter
<p><strong>Cortisol</strong></p>

<p>Cortisol is a hormone similar to adrenaline that is used in emergencies. One of its effects is to shut down the immune system for a short period (while that emergency lasts) to save energy (there's no need for that when the lion chases you).</p>

<p>(Mis)using this effect, long-term stress can cause your immune system to be reduced, and make you sick. Panicking about a situation over which you have no control but plenty of information (e.g. the Covid-19 pandemic where the only defence is your immune system and reducing the risk of getting it) could cause more harm than less information.</p>

<p>Sleeping more helps the immune system, but stress could disrupt that as well.</p>

CC BY-SA 4.0
2020-02-26T18:50:18.847Z
This seems at least analogous to world economics, but would benefit from some sources to back it up.
ti7
CC BY-SA 4.0
2020-02-27T13:52:38.453Z
What does this have to do with information?
Criticize SE actions means ban
CC BY-SA 4.0
2020-02-28T07:50:40.653Z
@user253751 Knowing about a pandemic can cause your immune system to be less capable of fighting the infection off. However, it's a weak argument - it also means you can be more careful with hygiene, avoid sick people, take disease more seriously (instead of e.g. going to work) etc. Those can be behaviors that aren't usually worth their costs, but are much more worthwhile with a dangerous pandemic around. My post-com country has plenty of history with officials preventing the spread of information for similar non-reasons, resulting in e.g. toxic chemicals remaining in foods for decades.
Luaan
CC BY-SA 4.0
2020-02-25T12:46:43.443Z
2020-02-25T12:46:43.443Z
Nyos
<p>More information is usually considered "better". Let's say a rational agent chooses optimally given his information on the circumstances of a particular decision problem. Then providing him with more or better information makes him (weakly) better off. </p>

<p>Other agents might be made worse off in the process, and total welfare might even decrease. Danove et al. (2003) e.g. argue that the introduction of mandatory "report cards" in New York and Pennsylvania in the 1990ies to evaluate bypass surgeries reduced welfare because it incentivized doctors to avoid treating very old or sick patients. In this example all patients got more information, and some of them, but not all, ended up worse off.</p>

<p>But there are also circumstances where providing agents with more information makes <strong>everybody</strong> worse off. When visitors are about to leave a crowded theater, truthfully informing them that a fire just broke out behind the curtain might have disastrous consequences for all of them. Informing the public that a particular bank is in trouble could trigger a bank run that leaves everybody worse off.</p>

<p><strong>What are other such phenomena?</strong> I am looking for examples (in theoretical models or in the real world) of the latter kind, where exogenously providing a group of agents with more or better information leads to a new equilibrium which is Pareto inferior compared to the old one.</p>

CC BY-SA 4.0
2020-02-24T22:12:51.410Z
See also "Reverse Tinkerbell Effect"
CodyBugstein
CC BY-SA 4.0
2020-02-25T12:34:46.940Z
Does this information need to be objectively true? I can list a lot of cases, when floods of lies can be disadvantageous.
Nyos
CC BY-SA 4.0
2020-02-25T13:41:44.260Z
@Nyos: Yes, in my understanding "information" is by definition true, otherwise I'd rather call it disinformation.
VARulle
CC BY-SA 4.0
2020-02-25T17:04:07.720Z
@VARulle The two cases that you mentioned are not fulfilling your criteria: in a theater fire there are potentially people that are better off, those who didn't fall victims to the stampede and managed to exit because of the alarm. In case of a bank run most people are worse off, but not the first ones who withdraw their full balance.
user3819867
CC BY-SA 4.0
2020-02-25T21:26:13.143Z
I don't have enough reputation for an answer, so leaving this as a comment. How about an old marriage? Both parties have occasional thoughts that they might be happier with someone else (because they're human and we all have these thoughts), but are happier together than they would be if they divorced. But if they each knew how often their partner had occasional stray thoughts, they might end up agreeing to a divorce, leaving them both worse off.
CPomerantz
CC BY-SA 4.0
2020-02-26T08:38:51.520Z
@CPomerantz: You need reputation to answer questions? I thought it is the other way round... As for your answer, thx--this is an interesting example, since here ins some sense your utility depends directly on your knowledge.
VARulle
CC BY-SA 4.0
2020-02-26T08:59:54.080Z
@user3819867: I don't think that just escaping the stampede makes you strictly better off compared to leaving the theater quietly--at the very least you will have to run, which is costly. It's similar for the bank run example.
VARulle
CC BY-SA 4.0
2020-02-26T12:21:41.280Z
@VARulle If people are not told there is a fire, why would they leave?
user3819867
CC BY-SA 4.0
2020-02-26T13:25:44.037Z
More generally beyond the theatre example it's any information that induces mass panic, such as knowing the full detail about any/ every asteroid heading towards Earth right now, the extent of spies within your community (i.e. if it turned out you live in a society like East Berlin with spies everywhere you'd be a lot more isolated), etc. Similarly knowing what people voted for in an election can result in potential avenues for bribery and therefore more corruption in the democratic process.
Luke Briggs
CC BY-SA 4.0
2020-02-26T15:44:10.580Z
@VARulle I have 100 rep because I have enough rep on other Stack Exchange sites. But you need 10 rep earned on this Stack Exchange to answer because it's a "Highly Active Question".
CPomerantz
CC BY-SA 4.0
2020-02-26T19:31:47.837Z
To whoever upvoted my comment, I appreciate it but it doesn't reward reputation. I will have to wait until the question is un-protected to write an answer.
CPomerantz
CC BY-SA 4.0
2020-02-26T20:58:27.787Z
Here is an interesting somewhat-fantasy-like story about a few pieces of "information" (statements) that could basically destroy the world, so not knowing of their existence is better for everyone: https://slatestarcodex.com/2018/10/30/sort-by-controversial/
Fabian Röling
CC BY-SA 4.0
2020-02-27T08:58:37.420Z
@user3819867, because the show is over. That's why I wrote "... are about to leave ...".
VARulle
CC BY-SA 4.0
2020-02-27T16:09:11.510Z
I suppose that "mandatory report cards" refers to [health care ratings](https://en.wikipedia.org/wiki/Health_care_ratings)? In that case the information released is misleading. Complete information in a "hospital report card" would include *who* had surgery there and would be normalized by patient risk.
Peter - Reinstate Monica
CC BY-SA 4.0
2020-02-28T07:38:26.783Z
You can always control people by controlling which pieces of information you share. If I tell you A, D and F, you might be worse off than if I didn't tell you anything; but if you learn B, C and E, you will be better off overall. Does this count as "more information is worse" or "more information is better"? :) One solution to information being harmful is restricting access to the information; another is providing _even more_ information. The former is probably warranted sometimes ("how to build a nuke at home in seven easy steps") :) Would the latter count for your question or not?
Luaan
CC BY-SA 4.0
2020-02-28T08:55:05.823Z
@Luaan, probably not. An agent building a nuke at home would benefit from doing so (by revealed preference), unless you assume that he is irrational or misinformed to begin with. But then there are many trivial such examples even in single-agent decision problems, which is not that interesting.
VARulle
CC BY-SA 4.0
2020-03-05T19:17:19.947Z
The question is still protected, so I still can't answer, but I came across another interesting example in daily life recently. It's similar to my previous comment answer in that it deals with interpersonal relations, but this actually happened in real life. Two (American) friends, one is a Republican the other is a Democrat. As long as they don't know that, their friendship is great. As soon as they start talking about politics and discover their political difference, they start constantly arguing and the friendship falls apart, leaving them both worse off.
CPomerantz
<game-theory><utility><information>
What are examples for the phenomenon that more (or better) information makes everybody worse off?
VARulle
# What are examples for the phenomenon that more (or better) information makes everybody worse off?

(Asked by: username_0 on 2020-02-24)

More information is usually considered "better". Let's say a rational agent chooses optimally given his information on the circumstances of a particular decision problem. Then providing him with more or better information makes him (weakly) better off.

Other agents might be made worse off in the process, and total welfare might even decrease. Danove et al. (2003) e.g. argue that the introduction of mandatory "report cards" in New York and Pennsylvania in the 1990ies to evaluate bypass surgeries reduced welfare because it incentivized doctors to avoid treating very old or sick patients. In this example all patients got more information, and some of them, but not all, ended up worse off.

But there are also circumstances where providing agents with more information makes **everybody** worse off. When visitors are about to leave a crowded theater, truthfully informing them that a fire just broke out behind the curtain might have disastrous consequences for all of them. Informing the public that a particular bank is in trouble could trigger a bank run that leaves everybody worse off.

**What are other such phenomena?** I am looking for examples (in theoretical models or in the real world) of the latter kind, where exogenously providing a group of agents with more or better information leads to a new equilibrium which is Pareto inferior compared to the old one.

**Tags:** game-theory, utility, information
> **Comments:**
> **username_1**: See also "Reverse Tinkerbell Effect"  
> **username_2**: Does this information need to be objectively true? I can list a lot of cases, when floods of lies can be disadvantageous.  
> **username_0**: @Nyos: Yes, in my understanding "information" is by definition true, otherwise I'd rather call it disinformation.  
> **username_3**: @VARulle The two cases that you mentioned are not fulfilling your criteria: in a theater fire there are potentially people that are better off, those who didn't fall victims to the stampede and managed to exit because of the alarm. In case of a bank run most people are worse off, but not the first ones who withdraw their full balance.  
> **username_4**: I don't have enough reputation for an answer, so leaving this as a comment. How about an old marriage? Both parties have occasional thoughts that they might be happier with someone else (because they're human and we all have these thoughts), but are happier together than they would be if they divorced. But if they each knew how often their partner had occasional stray thoughts, they might end up agreeing to a divorce, leaving them both worse off.  
> **username_0**: @CPomerantz: You need reputation to answer questions? I thought it is the other way round... As for your answer, thx--this is an interesting example, since here ins some sense your utility depends directly on your knowledge.  
> **username_0**: @user3819867: I don't think that just escaping the stampede makes you strictly better off compared to leaving the theater quietly--at the very least you will have to run, which is costly. It's similar for the bank run example.  
> **username_3**: @VARulle If people are not told there is a fire, why would they leave?  
> **username_5**: More generally beyond the theatre example it's any information that induces mass panic, such as knowing the full detail about any/ every asteroid heading towards Earth right now, the extent of spies within your community (i.e. if it turned out you live in a society like East Berlin with spies everywhere you'd be a lot more isolated), etc. Similarly knowing what people voted for in an election can result in potential avenues for bribery and therefore more corruption in the democratic process.  
> **username_4**: @VARulle I have 100 rep because I have enough rep on other Stack Exchange sites. But you need 10 rep earned on this Stack Exchange to answer because it's a "Highly Active Question".  
> **username_4**: To whoever upvoted my comment, I appreciate it but it doesn't reward reputation. I will have to wait until the question is un-protected to write an answer.  
> **username_6**: Here is an interesting somewhat-fantasy-like story about a few pieces of "information" (statements) that could basically destroy the world, so not knowing of their existence is better for everyone: https://slatestarcodex.com/2018/10/30/sort-by-controversial/  
> **username_0**: @user3819867, because the show is over. That's why I wrote "... are about to leave ...".  
> **username_7**: I suppose that "mandatory report cards" refers to [health care ratings](https://en.wikipedia.org/wiki/Health_care_ratings)? In that case the information released is misleading. Complete information in a "hospital report card" would include *who* had surgery there and would be normalized by patient risk.  
> **username_8**: You can always control people by controlling which pieces of information you share. If I tell you A, D and F, you might be worse off than if I didn't tell you anything; but if you learn B, C and E, you will be better off overall. Does this count as "more information is worse" or "more information is better"? :) One solution to information being harmful is restricting access to the information; another is providing _even more_ information. The former is probably warranted sometimes ("how to build a nuke at home in seven easy steps") :) Would the latter count for your question or not?  
> **username_0**: @Luaan, probably not. An agent building a nuke at home would benefit from doing so (by revealed preference), unless you assume that he is irrational or misinformed to begin with. But then there are many trivial such examples even in single-agent decision problems, which is not that interesting.  
> **username_4**: The question is still protected, so I still can't answer, but I came across another interesting example in daily life recently. It's similar to my previous comment answer in that it deals with interpersonal relations, but this actually happened in real life. Two (American) friends, one is a Republican the other is a Democrat. As long as they don't know that, their friendship is great. As soon as they start talking about politics and discover their political difference, they start constantly arguing and the friendship falls apart, leaving them both worse off.  

---

## 9 answers

### Answer by username_13 on 2020-02-25. Score: 11

The “to be announced” or TBA market for agency mortgage-backed securities is a great example of this.

The short version is as follows: The TBA market is a market wherein one can purchase or sell for future delivery pools of mortgages that conform to certain characteristics (e.g., and to vastly simplify, 30 year mortgages at a 4.5% coupon) without specifying the particular mortgages to be delivered. Only government- or agency-guaranteed mortgages are eligible for TBA delivery. Of course, the incentive is for the pool seller to deliver the worst mortgages possible, but “worst” is entirely based on the mortgages’ prepayment characteristics, not on their credit quality (as they’re all guaranteed).

Why is this good? It makes for a really liquid market, because everyone just prices everything assuming it is bad. Buyers don’t waste a bunch of time trying to analyze pools trying to uncover some marginal advantage, because that’s simply not an option. So they can buy securities in this market blindly, knowing that they’re only being shortchanged in the selection of mortgages in the pools they buy to a predictable degree that is already priced into the market. This is really useful given that most of the buy side doesn’t have a ton of resources to spend on pool-level evaluations.

The result: a multi-trillion dollar market in annual primary volume (not counting financing that occurs in this market), that is estimated to be responsible for reducing the cost of mortgage financing in the US by [10-25bps on average](https://www.newyorkfed.org/medialibrary/media/research/epr/2013/1212vick.pdf).

> **Comments:**
> **username_14**: So basically, everyone having *less* information makes everyone *better* off?  
> **username_13**: Yes, which also means that if they had *more* information, they would be *worse* off (which is true for non-TBA-eligible securities).  
> **username_8**: Except it only _looks_ like you're better off, because _somebody else is paying the bill_. The guarantee simply makes the information _irrelevant_ - it overrides the _reasons_ why the information is (normally) useful; instead of you being responsible for the quality of your investment, if you make a mistake, the taxpayers pay for it - essentially, you're handing everyone's money to pay for the past times/investments of a part of the population.  
> **username_13**: @Luaan You’ve clearly not read the linked paper or any of the relevant literature on this topic. The estimated liquidity benefit is comparing guaranteed TBA-eligible securities to *also guaranteed* non-TBA eligible securities. What is being valued is *not the guarantee at all*.  
> **username_8**: No, it just says that if you can have general buy and sell orders, and somebody else guarantees the commodity being bought and sold, you will have a better performing market than if you can't have general buy orders. The liquidity isn't enhanced by the lack of information, it's enhanced because you _get_ the information - how much people are willing to give you for a given commodity, regardless of how good an investment it is. The information "there's 20 people willing to pay me $20 for X" is more valuable than "there's 1 willing to pay $23 for X1, 3 who pay $26 for X2, ..."  
> **username_13**: @Luaan You’re correct that the liquidity comes in part from less specificity in orders but you are missing something important: the guarantee itself does not make the underlying securities the same. They still differ significantly in their interest rate characteristics and thus their underlying value. The TBA cheapest-to-deliver feature is *also* destroying information, in addition to the guarantee. I ask that you please read the reference provided. I’m happy to provide more.  

---

### Answer by username_15 on 2020-02-24. Score: 11

This sounds glib, but The Internet is an ongoing example.

In economic models where access to information is an explicit factor, we often gloss over the fact that mere exposure to information about the state of the world is not enough to improve welfare - one also needs the cognitive skills to use those facts to develop plans in support of preferences, and also the abilities necessary to manipulate the environment in execution of those plans. *Homo economicus* is implicitly assumed to possess both, but this is manifestly untrue about *Homo sapiens*. "The Death of Expertise" by Tom Nichols is a good first-look at the scope of the problem, viewing the interplay between limited human capacities and unfettered access to information ("signals", really) through a sociological lens. The Dunning-Kruger effect and the competition between identity/belonging goals and accuracy goals are two key elements to this.

If you want to get deeper into it, a host of other empirically-supported cognitive biases - anchoring, affect heuristic, availability bias, and so-on - suggest that the phenomenon of acting in response to an information set that becomes more complete with time exhibits hysteresis. This is tremendously problematic when recognizing that while *Homo economicus* is presumed to hold all of the available information in her head in one simultanous pre- $t = 0$ moment, each of the information sets held by every *Homo sapiens* carries a slightly different history than any other. To the extent that these information sets are compiled by experiencing signals available on the Internet, *a proiri* one should expect that a bigger pool of signals will yield a wider variation in the histories, and less rather than more concensus about the state of the world and which actions (usually requiring the solution of co-ordination problems) might lead to greater social welfare.

> **Comments:**
> **username_8**: Is this fair, though? Of course _wrong_ information, or information that is improperly interpreted can be bad for you, but that's not exactly a paradox, is it? If I lie to you to make you send me a million dollars, it's not a problem of having too much information, but rather too little :) Indeed, a common way of manipulating people is to tell the truth, but at the same time withhold critical information that puts the truth in context etc. We're dealing with probabilities here - is there correct, well interpreted information that _on average_ gives you worse outcomes than not knowing?  
> **username_15**: Well this is why I prefer to use the term "signal" rather than "information".  It is also why I include the importance of *having the skill to act*.  Without that, even true signals can lead to sub-optimal outcomes.  And finally, it seems like you're still clinging to the assumption that all pertinent information is available pre-$t = 0$; this simply isn't true.  We receive a stream of signals that evolves throughout time, and so by definition it will always be incomplete - and some of that missing data will be "critical" in the sense you mean it.  There is no real counterfactual to that.  
> **username_16**: Piggybacking off the internet example - any time there are costs to processing the signal, such as agents having limited cognitive load, it is possible to provide "too much information."  

---

### Answer by username_9 on 2020-02-25. Score: 8

The post of @Mmmmmm about traffic reminded me of [Braess's Paradoxon](https://en.wikipedia.org/wiki/Braess%27s_paradox): There are situations in a traffic network (under the assumption that all drivers are rational) where *removing* some roads leads to a lower average amount of time spent driving.

While the paradox itself was constructed with another goal in mind it assumes that all drivers know the optimal path to take.

> **Comments:**
> **username_10**: Note that you can also adapt this example to the question: The road does not have to be removed in reality but only from the knowledge of all drivers.  

---

### Answer by username_11 on 2020-02-25. Score: 6

[Paul Krugman](https://www.nytimes.com/2020/02/20/opinion/warren-bloomberg-debate.html) recently discussed the [Bloomberg terminal](https://en.wikipedia.org/wiki/Bloomberg_Terminal), a classic example of a resource with the following properties:

1. Those who get it are at an advantage, so naturally everyone gets it;
2. It's not free, so everyone getting it cancels out the benefits, making everyone worse off.

The world must be full of examples of this. Dave Gorman once mentioned another example, where everyone on his flight, him included, had paid for priority boarding. You can guess what happened.

> **Comments:**
> **username_0**: Looks like a classical public goods game, but I don't think it qualifies as an example where providing all agents with more information makes everybody worse off. The extra information has to be purchased here and is not simply provided to everyone (for free). If it were, then everybody would end up as well off as before (assuming that you profit only from an informational advantage over others).  
> **username_12**: Another classic example: health insurance.  
> **username_8**: @user560822 There's nothing wrong with health insurance in general - it's a service that allows you to trade risks and large sudden sums of money for regular payments. It's no different from taking a loan, for example. What you're thinking of is the "bonuses" health insurance companies try to give their customers to choose their particular company, and which are the main reason the US health system is such a mess - e.g. having doctors increase base-line prices, just so the insurance company can give "discounts" for their customers even though they're just paying the market price.  
> **username_8**: The thing is, if people stop doing that, it will become advantageous again - which balances out the information value. If enough people learn there's no point in having priority boarding, it will become useful again :) This is just an example of sub-optimal Nash equilibrium - everyone would be better off if noone did it, but every individual will be at a loss for being the one not to do it. Heck, it's well known in evolutionary biology - trees only benefit from growing so tall because other trees are tall; all trees would be better off shorter, but can't afford to be.  
> **username_7**: Arguably, Bloomberg terminals are an example for *withholding* information (and then releasing it only for a fee), so it could actually be a counter-example. If everybody had perfect market information the market would be closer to perfect; optimal markets again lead to optimal resource allocation which improves overall welfare.  
> **username_12**: @Luaan Health insurance removes the incentive for care providers to compete on price and replaces it with a perverse incentive to charge the maximum allowed. This drives up prices until nobody can afford health care without insurance, so everyone wants insurance, to everyone's detriment. There is no "market price" for health care as long as insurance is legal. It's a perfect example of what this answer is about.  
> **username_8**: @user560822 No, it doesn't. And it didn't for a quite a while even in the US. Insurance companies put pressure on health care providers to lower their prices (and avoid unnecessary _covered_ diagnostics/treatment etc.). Of course, it's a layer of indirection, and that has costs. Add that many companies started paying the health insurance of their employees as a benefit, and you have _another_ layer of indirection. The absurdity in the US system is that, as you correctly pointed out, the health care prices aren't market prices - they're a signalling cheat saying "insurance is cheaper!"  
> **username_12**: @Luaan The insurance company pressures for lower prices to increase their own profits. A functional market would force prices *at least* as low, and probably much lower, because consumers would have vastly more freedom of choice. Insurance is intentionally designed to limit consumer freedom as well as consumer knowledge.  

---

### Answer by username_17 on 2020-02-25. Score: 3

This is a very old idea in general equilibrium models with imperfect information and incomplete markets.
More information could be detrimental if the agents that face uncertainty situations decide to insure and the equilibrium under full insurance is pareto optimal.

If in such a situation the state would be revealed with a perfectly informative signal the state of nature would be known before the opening of the market and so the insurance possibilities for the agents are destroyed.

Take a look at these links:

* [Hirshleifer (1973)](https://www.jstor.org/stable/pdf/1817048.pdf?casa_token=ayB-QLEbbIAAAAAA:P-x4m1r4lv5ateQXs2B91pjHyY7yx8NPPZZu-x1BXzcQlJYknCA8k_Xf0UwokCM-AGit8QM-62_dBGTTp8JJ1jv00xL9cneq7sUWCAH7j2rlVQRrIwNveg)
* [Information Economics By Urs Birchler, Monika Bütler](https://books.google.it/books?id=vppTCIGyoK4C&pg=PA301&lpg=PA301&dq=destruction%20of%20insurance%20possibility%20and%20reduced%20welfare&source=bl&ots=ydL-bQ-6ze&sig=ACfU3U0xIEJDiKWAfD9ZGD0rX0V6qE_PFw&hl=en&sa=X&ved=2ahUKEwj7x-_jmu3nAhUVQkEAHTLRABEQ6AEwAnoECAcQAQ#v=onepage&q=destruction%20of%20insurance%20possibility%20and%20reduced%20welfare&f=false)

there was also another example in eeckhoudt, gollier and schlesinger "Economic And Financial Decisions Under Risk" but I cannot find it right away.

**EDIT**: @Giskard Example:
Think about an example where you have two consumers with concave utility functions and endowments $ \omega\_1=(1,0) $ and $\omega\_2=(0,1)$ and state dependent utilities that assign 0 utils to the consumption of one of the two goods in one of the two states.

With the same utility functions and same endowments the economy is in an edgeworth box and as long as the agents are risk adverse they would like full insurance i.e. they will choose a point on the 45degree line with same consumption in the two states.

However, if a perfect signal reveals the state of nature before the spot market opens the guy that has the "bad" good cannot insure anymore because this economy doesn't satisfy the minimal revenue condition and there would be no trade. Overall, the concavity of the utilities and the decreasing returns of consumption guarantee that the welfare is higher in the case of full insurance than under perfect information.

This could be the case in a very simplified economy where the endowments are two different antivirals and only one virus (state) will attack (realize in) our fantasy world. But I have read also a conceptually very similar example on the insurance market in the book that I cited.

**EDIT 2**: Taking back Mas-colell book I have found this:
[![enter image description here](https://i.sstatic.net/a7hKD.png)](https://i.sstatic.net/a7hKD.png)
you could look into Spence (1973) signalling model where even if the signal is not costly could create such a problem!

> **Comments:**
> **username_18**: I have read the second book (several years back), but I still do not understand what you mean. Why is it bad that the insurance possibilities are destroyed? If you already know everything, you don't need ex post insurance? And ex ante insurance is not destroyed.  
> **username_0**: In your example total welfare might decrease, but the situation with information on the state of nature doesn't seem to be Pareto inferior to the one without information. The agent with the "good" good is not made worse off by revealing the state of nature.  
> **username_17**: This comment really surprises me. Total welfare may be in doubt (it will depend from the exact curvature of the utilities), but for sure the certain situation is a pareto deprovement. The "bad" agent has utility of zero so is obviously worse off and it is not a pareto improvement.  
> **username_0**: @KArrow'sBest: Well, for being Pareto inferior compared to the certainty situation both agents would have to be strictly worse off.  
> **username_17**: @VARulle, I know the definition. I believe, that also the agent with the "good" good would be worse off if both states at t=0 (before the signal) have p=.5 he will loose half of the time and will end-up with expected utility lower than the case with full insurance.  
> **username_0**: @KArrow'sBest, I don't agree. The agent with the "good" good wins by definition, so he cannot "lose half of the time". Let's normalize $u(0)=0$ and $u(1)=1$. You seem to be comparing ex-ante expected utilities which are $Eu_i=u(1/2)>1/2$ for both without information and $Eu_i=1/2$ for both with information. What I mean with "being made worse off" by being informed is a causal chain, so you have to compare the respective ex-post utilities. But those will be $u_i=1$ and $u_{-i}=0$ with information, which is not Pareto inferior to $u_i=u_{-i}=u(1/2)$ without information.  
> **username_17**: @VARulle Thanks for the numeric example, I also had this approach the first time I have seen the example and at a first sight may be correct. However, it is enough to modify the trade to be repeated $n$ times with the same conditions each time, to have the no information case as a pareto improvement of the one with signals, and it is given the concavity of $u()$. I think I have studied this exact example in mas-colell advanced micro, either in chapter 6 or 19.  
> **username_0**: @KArrow'sBest: Yes, you're right, I finally understand what you mean. Nice example, thx!  

---

### Answer by username_19 on 2022-10-16. Score: 0

Let me contribute. Excessive and unnecessary innovation in science and technology is an example where better information makes everybody worse off.

Excessive Innovation: smartphones with apps that spoiled our lives. Endless cheap entertainment such as Youtube contents (very cheap, by swiping the phone screen), Instagram contents, etc. Online smartphone games. These free service makes less educated people less intelligent and impatience (instant services provided by smartphones can develop a habit that you expect thing to be done instantly). This does not apply to everyone of course (for example: a highly occupied person may be distracted against using smartphones)

Unnecessary Innovation: the advancement of Artificial Intelligence and open source give power to any person (good or bad). It can be abused by making fake political videos, fake videos to criminalize someone, erotic robots, fake humans (robots).

Atomic bomb is also another example. Which is the result of some information or knowledge on physics.

\*Please debate my arguments, I would appreciate it.

> **Comments:**
> **username_0**: It can be debated if these are really examples where everybody (!) is made worse off. But even if this is granted, the reason seems to be that individuals are lured into doing things that make them worse off. Rational agents (which I assumed in my question) wouldn't do that.  

---

### Answer by username_3 on 2020-02-25. Score: 0

## Cases where the information increases perceived value but not real value

Information that can only be used for harming others and/or self are generally not helping the broad public.  
The ongoing [efforts to pursue 3D printed guns](https://www.vox.com/2018/7/31/17634558/3d-printed-guns-trump-cody-wilson-defcad) is one of such topics; while you may argue that some people in certain cases benefit from them, they are generally undesirable as knowledge.  
Even more so, public information on nuclear devices can [ruin a person's life](https://en.wikipedia.org/wiki/David_Hahn) while not likely making anyone better off.

> **Comments:**
> **username_14**: So basically the fact that everyone is better off when nobody has guns than when everyone has a gun (even though every individual person is better off having a gun), but where the source of the guns is information? Yeah, that works.  

---

### Answer by username_20 on 2020-02-24. Score: -1

Not an exact example but here's a case when omniscience is a disadvantage.

Suppose I'm playing a game of chicken where I'm driving straight at an opponent and whoever swerves first loses. If I know my opponent is omniscience or can read my mind [and doesn't have a death wish], then I can confidently conclude that I need never swerve. My opponent will read my mind and realize that I will never swerve, and hence realize he be the one who has to swerve.

> **Comments:**
> **username_21**: In your example, more information does not make *everybody* worse off.  
> **username_22**: @HerrK. Ok, what if both you *and* your opponent are omniscient?  
> **username_21**: @Andy: Then one of the Nash equilibria will be played. But I still don't see how that hurts both players.  

---

### Answer by username_2 on 2020-02-25. Score: -2

**Cortisol**

Cortisol is a hormone similar to adrenaline that is used in emergencies. One of its effects is to shut down the immune system for a short period (while that emergency lasts) to save energy (there's no need for that when the lion chases you).

(Mis)using this effect, long-term stress can cause your immune system to be reduced, and make you sick. Panicking about a situation over which you have no control but plenty of information (e.g. the Covid-19 pandemic where the only defence is your immune system and reducing the risk of getting it) could cause more harm than less information.

Sleeping more helps the immune system, but stress could disrupt that as well.

> **Comments:**
> **username_23**: This seems at least analogous to world economics, but would benefit from some sources to back it up.  
> **username_14**: What does this have to do with information?  
> **username_8**: @user253751 Knowing about a pandemic can cause your immune system to be less capable of fighting the infection off. However, it's a weak argument - it also means you can be more careful with hygiene, avoid sick people, take disease more seriously (instead of e.g. going to work) etc. Those can be behaviors that aren't usually worth their costs, but are much more worthwhile with a dangerous pandemic around. My post-com country has plenty of history with officials preventing the spread of information for similar non-reasons, resulting in e.g. toxic chemicals remaining in foods for decades.  

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