In Western Philosophy, language has long been closely associated with reason, which is also a uniquely human way of using symbols. (In Ancient Greek philosophical terminology, the same word, logos, was used for both language and reason.) Language refers only to expressions of reason which can be understood by other people, most obviously by speaking.

Properties of language

A set of commonly accepted symbols is only one feature of language; all languages must define the structural relationships between these symbols in a system of grammar. Rules of grammar are what distinguish language from other forms of communication. They allow a finite set of symbols to be manipulated to create a potentially infinite number of grammatical utterances.

Another property of language is that its symbols are arbitrary. Any concept or grammatical rule can be mapped onto a symbol. Most languages make use of sound, but the combinations of sounds used do not have any inherent meaning – they are merely an agreed-upon convention to represent a certain thing by users of that language. For instance, there is nothing about the Spanish word lang: nada itself that forces Spanish speakers to convey the idea of "nothing". Another set of sounds (for example, the English word nothing) could equally be used to represent the same concept, but all Spanish speakers have acquired or learned to correlate this meaning for this particular sound pattern. For Slovenian, Croatian, Serbian or Bosnian speakers on the other hand, lang: nada means something else; it means "hope".

This arbitrariness does not, however, apply to words with an onomatopoetic dimension (i.e. words that to some extent simulate the sound of the token referred to). For example, the bird cuckoo's name was indeed not given arbitrarily.

Origins of language

main: Origin of language Even before the Theory of Evolution made discussion of more animal-like human ancestors common place, philosophical and scientific speculation concerning the origins of language, implying that human ancestors once had no language, have been frequent throughout history. In modern Western Philosophy, speculation by authors such as Thomas Hobbes, and later Jean Jacques Rousseau lead to the Académie Francaise even declaring the subject off bounds.

The subject is of such interest to philosophy because language is such an essential characteristic of humans. In Classical Greek Philosophy such questions were connected to the subject of the Natures of things, in this case "Human Nature". Therefore already in Aristotle we see language being mentioned in discussions of natural propensities of humans to be political and to dwell in city state types of communities, pair-bonding, poetical and so on.