Where is there the energy that changes language?

I was born in 1947 and become 68 years old this summer.
My unripeness to language study has come to the declining years.
Return to physics or mathematics is almost alike to back to youth age, when almost every day solving rudimentary problems for entire interest to unknown world.

In my mind there still are some hard themes to challenge, one of which is energy in language. The theme is originated from Edward Sapir, who presented the concept "drift" in Language, 1921. 
It was the macro and intuitive concept that was supposed by his precise thinking and vast field work of American native's language. I think that I would develop the theme from the physics-mathematics field.

In the garden

Peony begins to come out in the early spring

as though overcoming wintry coldness.

If there be change in language, from which to which language changes in its true nature?

Where is there the energy that changes language?

Reference:

Substantiality, Dedicated SAPIR Edward / 27 February 2005

Tokyo

22 February 2015

SIL