<P> More generally, reason in the strict sense requires the ability to create and manipulate a system of symbols, as well as indices and icons, according to Charles Sanders Peirce, the symbols having only a nominal, though habitual, connection to either smoke or fire . One example of such a system of artificial symbols and signs is language . </P> <P> The connection of reason to symbolic thinking has been expressed in different ways by philosophers . Thomas Hobbes described the creation of "Markes, or Notes of remembrance" (Leviathan Ch. 4) as speech . He used the word speech as an English version of the Greek word logos so that speech did not need to be communicated . When communicated, such speech becomes language, and the marks or notes or remembrance are called "Signes" by Hobbes . Going further back, although Aristotle is a source of the idea that only humans have reason (logos), he does mention that animals with imagination, for whom sense perceptions can persist, come closest to having something like reasoning and nous, and even uses the word "logos" in one place to describe the distinctions which animals can perceive in such cases . </P> <P> Reason and imagination rely on similar mental processes . Imagination is not only found in humans . Aristotle, for example, stated that phantasia (imagination: that which can hold images or phantasmata) and phronein (a type of thinking that can judge and understand in some sense) also exist in some animals . According to him, both are related to the primary perceptive ability of animals, which gathers the perceptions of different senses and defines the order of the things that are perceived without distinguishing universals, and without deliberation or logos . But this is not yet reason, because human imagination is different . </P> <P> The recent modern writings of Terrence Deacon and Merlin Donald, writing about the origin of language, also connect reason connected to not only language, but also mimesis, More specifically they describe the ability to create language as part of an internal modeling of reality specific to humankind . Other results are consciousness, and imagination or fantasy . In contrast, modern proponents of a genetic pre-disposition to language itself include Noam Chomsky and Steven Pinker, to whom Donald and Deacon can be contrasted . </P>

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