[SideburnsOfDoom]

A lot of academic programming language research is an outgrowth of mathematics, so it uses the language of mathematics.

E.G "boolean" dates back to George Boole, The Mathematical Analysis of Logic (1847)

https://en.wikipedia.org/wiki/Boolean_algebra#History

and "lambda" to Alonzo Church in the 1930s

https://en.wikipedia.org/wiki/Lambda_calculus