The basis of language is not “metaphor,” sorry Lakoff. Metaphor is a linguistic (or maybe pre-linguistic) category, but it does not beget language.
Neither is language “inherent programming” (sorry Chomsky)…at least, not for language in itself. Again, a capacity developed, but not a structural girder.
How can I say such a thing??!! Because we have cases of humans who survived fine without language. At least, till “civilized” people got their hands on them.
Maybe these “scientists” never had children, or were too busy making up “science” to pay attention.
A child develops language first through rhythm. Rhythm is an organismic response to habitat – first, the land; second, human habitat (machines (read about Dave Brubeck), physical structures (shoebox or hut?), and culture).
Music. Then imitation. Sound play. Along the way, association.
Beneath it all, the land.
In your car or house, sing along very loudly and get the physiological sense of the tone you’re making.
Get to it.