Natural symbols

From the beginning of his semiotic work — before he called it that — C.S. Peirce recognized three kinds of sign: icon, index and symbol. Symbolic signs are essential to human language, and that makes all the difference between language and other kinds of communication found in nature. Peirce wrote in 1909 that symbols ‘represent their objects, independently alike of any resemblance or any real connection, because dispositions or factitious habits of their interpreters insure their being so understood’ (EP 2:461). A language is a complex set of habits common to all who speak the language. ‘Factitious habits’ are artificial conventions; ‘dispositions’ however need not be artificial. Obviously the primary reference here is to the use of language, which is partly conventional, but not entirely so in the case of ‘natural languages’: the ‘dispositions’ which guide the interpretive process can be as deeply grounded in human nature as the habits of laughing, crying or smiling.

And what about the larger natural context of human nature? Could the dispositions of language-interpreters be grounded in pre-linguistic habits? Is there a kind of interpretation older than language, a kind of symbol older than humanity? What about the genome: it is obviously a sign of the organism, but can we call it a symbol?

The analogy between genetic and linguistic structures has been made many times, because both are modular and combinatorial. That is, the molecular structures within the genome consist of parts which hang together as units and can be rearranged to generate a somewhat different organism, just as a new arrangement of word-symbols can mean something new. (Of course there are constraints on this rearranging — not every structure is viable in either domain, genetic or linguistic.) Both genetic and linguistic ‘statements’ are holarchic, i.e. they are multilevel structures, each level consisting of units which are both parts of larger wholes and wholes made up of their own parts. The main difference seems to be that statements in language are intentionally (consciously, deliberately) meant to be interpreted, while genetic ‘utterances’ are not. But is this an absolute difference, or are there levels of intentionality mediating between those two extremes? If so, then it's more than metaphor or analogy to say that genes are symbols.

There is of course a big difference between the interpretation of a linguistic sign and that of the genome, but not so big a difference that the latter can't be called interpretation.

Language is a social phenomenon, which means that the interpreter of a sign is a different person from its producer. We do talk to ourselves — usually not out loud — but you first learn to talk by interacting with others, and later internalize a virtual other as yourself, i.e. a self you can talk to while you're alone (we call this thinking, or internal dialogue).

The interpreter of your genome, on the other hand, is your biological self (rather than a social or virtual self). Each replica of the genome is read by the cell in which it is embedded, and the reading process is guided from without by indexical signs of the cell's environment. The collective interpretant of all these cellular-semiotic processes is the growth, differentiation, self-organization and behavior of your body — including your verbal behavior!

As with any linguistic utterance, the meaning of the genome is context-dependent. Why not, then, call it a symbol?