<human>: Until his return from Mexico in 1930 Whorf had been entirely an autodidact in linguistic theory and field methodology, yet he had already made a name for himself in Middle American linguistics. Whorf had met Sapir, the leading US linguist of the day, at professional conferences, and in 1931 Sapir came to Yale from the University of Chicago to take a position as Professor of Anthropology. Alfred Tozzer sent Sapir a copy of Whorf's paper on "Nahuatl tones and saltillo". Sapir replied stating that it "should by all means be published"; however, it was not until 1993 that it was prepared for publication by Lyle Campbell and Frances Karttunen.  Whorf took Sapir's first course at Yale on "American Indian Linguistics". He enrolled in a program of graduate studies, nominally working towards a PhD in linguistics, but he never actually attempted to obtain a degree, satisfying himself with participating in the intellectual community around Sapir. At Yale, Whorf joined the circle of Sapir's students that included such luminary linguists as Morris Swadesh, Mary Haas, Harry Hoijer, G. L. Trager and Charles F. Voegelin. Whorf took on a central role among Sapir's students and was well respected.  Sapir had a profound influence on Whorf's thinking. Sapir's earliest writings had espoused views of the relation between thought and language stemming from the Humboldtian tradition he acquired through Franz Boas, which regarded language as the historical embodiment of volksgeist, or ethnic world view. But Sapir had since become influenced by a current of logical positivism, such as that of Bertrand Russell and the early Ludwig Wittgenstein, particularly through Ogden and Richards' The Meaning of Meaning, from which he adopted the view that natural language potentially obscures, rather than facilitates, the mind to perceive and describe the world as it really is. In this view, proper perception could only be accomplished through formal logics. During his stay at Yale, Whorf acquired this current of thought partly from Sapir and partly through his own readings of Russell and Ogden and Richards. As Whorf became more influenced by positivist science he also distanced himself from some approaches to language and meaning that he saw as lacking in rigor and insight. One of these was Polish philosopher Alfred Korzybski's General semantics, which was espoused in the US by Stuart Chase. Chase admired Whorf's work and frequently sought out a reluctant Whorf, who considered Chase to be "utterly incompetent by training and background to handle such a subject." Ironically, Chase would later write the foreword for Carroll's collection of Whorf's writings.  If read superficially, some of Whorf's statements lend themselves to the interpretation that he supported linguistic determinism. For example, in an often-quoted passage Whorf writes:  We dissect nature along lines laid down by our native language. The categories and types that we isolate from the world of phenomena we do not find there because they stare every observer in the face; on the contrary, the world is presented in a kaleidoscope flux of impressions which has to be organized by our minds--and this means largely by the linguistic systems of our minds. We cut nature up, organize it into concepts, and ascribe significances as we do, largely because we are parties to an agreement to organize it in this way--an agreement that holds throughout our speech community and is codified in the patterns of our language. The agreement is of course, an implicit and unstated one, but its terms are absolutely obligatory; we cannot talk at all except by subscribing to the organization and classification of data that the agreement decrees. We are thus introduced to a new principle of relativity, which holds that all observers are not led by the same physical evidence to the same picture of the universe, unless their linguistic backgrounds are similar, or can in some way be calibrated.  The statements about the obligatory nature of the terms of language have been taken to suggest that Whorf meant that language completely determined the scope of possible conceptualizations. However neo-Whorfians argue that here Whorf is writing about the terms in which we speak of the world, not the terms in which we think of it. Whorf noted that to communicate thoughts and experiences with members of a speech community speakers must use the linguistic categories of their shared language, which requires moulding experiences into the shape of language to speak them--a process called "thinking for speaking". This interpretation is supported by Whorf's subsequent statement that "No individual is free to describe nature with absolute impartiality, but is constrained by certain modes of interpretation even when he thinks himself most free". Similarly the statement that observers are led to different pictures of the universe has been understood as an argument that different conceptualizations are incommensurable making translation between different conceptual and linguistic systems impossible. Neo-Whorfians argue this to be is a misreading since throughout his work one of his main points was that such systems could be "calibrated" and thereby be made commensurable, but only when we become aware of the differences in conceptual schemes through linguistic analysis.  Whorf's study of Hopi time has been the most widely discussed and criticized example of linguistic relativity. In his analysis he argues that there is a relation between how the Hopi people conceptualize time, how they speak of temporal relations, and the grammar of the Hopi language. Whorf's most elaborate argument for the existence of linguistic relativity was based on what he saw as a fundamental difference in the understanding of time as a conceptual category among the Hopi. He argued that the Hopi language, in contrast to English and other SAE languages, does not treat the flow of time as a sequence of distinct countable instances, like "three days" or "five years", but rather as a single process. Because of this difference, the language lacks nouns that refer to units of time. He proposed that the Hopi view of time was fundamental in all aspects of their culture and furthermore explained certain patterns of behavior. In his 1939 memorial essay to Sapir he wrote that "... the Hopi language is seen to contain no words, grammatical forms, construction or expressions that refer directly to what we call 'time', or to past, present, or future..."  Linguist Ekkehart Malotki challenged Whorf's analyses of Hopi temporal expressions and concepts with numerous examples how the Hopi language refers to time. Malotki argues that in the Hopi language the system of tenses consists of future and non-future and that the single difference between the three-tense system of European languages and the Hopi system, is that the latter combines past and present to form a single category.  Malotki's critique was widely cited as the final piece of evidence in refuting Whorf's ideas and his concept of linguistic relativity while other scholars defended the analysis of Hopi, arguing that Whorf's claim was not that Hopi lacked words or categories to describe temporality, but that the Hopi concept of time is altogether different from that of English speakers. Whorf described the Hopi categories of tense, noting that time is not divided into past, present and future, as is common in European languages, but rather a single tense refers to both present and past while another refers to events that have not yet happened and may or may not happen in the future. He also described a large array of stems that he called "tensors" which describes aspects of temporality, but without referring to countable units of time as in English and most European languages. CANNOTANSWER

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<bot>: Linguist Ekkehart Malotki challenged Whorf's analyses of Hopi temporal expressions and concepts