Language in Hand: Why Sign Came Before Speech
Then, just what about language does necessity rule, and where does chance come into it? We cannot go back to physicists for an answer to this one. Or perhaps we can. From physical laws and theories came the basis of the knowledge chemists have gained about the composition of things. Chemists’ findings enable biologists to understand anatomy, physiology, and genetics. Biologists guided by Darwin and many after him can tell us a great deal about chance and necessity.
About five million years ago, some apes came down out of trees and lived in new ways. Some of them must have differed—by chance, what else?—from their relatives left up there. Among the new breed too there must have been differences. There always are. These differences, one way or another, resulted in more of the odd ones’ offspring surviving. Given long enough, a new species that walked upright and was not as well adapted as the old for living in trees evolved. This origin of a new species happened more than once in those few million years. Fossils show that Australopithecines and a few species of genus Homo originated and became extinct (or evolved into others) in that long period. At the same time, however, gorillas, chimpanzees, and orangutans continued pretty much unchanged. Apparently they differed or departed less from our remote common ancestor’s physical form and way of behaving.
Necessity sees to it that parents’ genes largely determine their offspring’s physical form. And physical form necessarily influences behavior, what can be done and how. Chance has already entered as variation, as every parent knows who has two or more children (not identical twins). Siblings differ in many ways. Multiply that by the variation within offspring in one generation of a whole population or species and it’s clear that chance has ample room to work, generation after generation.
No question then. Necessity and chance, in the form of natural selection, produced the human species. We’re here, but so is language. And language is not physiology—or is it? Because language cannot be weighed or measured or even directly tied to the events we suppose it may have caused, some philosophers in every age have thought that language is separate from our bodies and everything else physical. Yet no evidence can be found for the separate existence of mind, spirit, soul, language, thought, concepts, and so on. They belong to us, inhabitants of this physical universe. Evidence keeps turning up that human brains, vision, hearing, and actions not only suffice but must be there for language. Necessity again. Language must have the human species, with all its chance or random variation, to operate in and on.