The cultural evolution of words and other thinking tools.

The emergence of language and culture is one of the major transitions in evolution (Maynard Smith and Szathmary 1995), and the key to the cumulative nature of cultural transmission in Homo sapiens as contrasted with other species is the digital nature of language, which permits semi-understood designed entities to be preserved and transmitted. Phonemes are not the only systems of self-correcting (digitized) norms; other "alphabets" of practices also contribute to high-fidelity preservation of cultural products.