Steven Pinker Quotes
I don't think language could have evolved if it was the only distinctive trait. It goes hand in hand with our ability to develop tools and technologies, and also with the fact that we cooperate with nonrelatives.
Pinker, Steven. The Language Instinct: How the Mind Creates Language. William Morrow and Company, 1994.
By symbols be was not only referring to metaphorical symbols of letters, words, digrams, numbers and formulas. The vast majority of all human knowledge is spread by symbols of one kind or another. The must sophisticated devices or weapons all boil down to sets of words, formulas and diagrams. Art is almost all symbolic.
Steven Arthur Pinker is a Canadian-American cognitive psychologist, linguist, and popular science author. He is an advocate of evolutionary psychology and the computational theory of mind.