I didn't like this tutorial. I don't think that using Lisp clarifies what is going on. They claim to show how numbers are created in lambda calculus, by defini

I didn't like this tutorial. I don't think that using Lisp clarifies what is going on. They claim to show how numbers are created in lambda calculus, by defining some lisp functions that call take a function and call it on itself n times (starting from... what?). And then they just use the builtin lisp function "inc" and claim this somehow shows how numbers are represented. That doesn't make any sense to me. They haven't shown how 45 is represented in lambda calculus. Is it just represented as "inc" called 45 times, starting from the number 0? If so, why is zero special? What is the connection between "inc" and representation of numbers in lambda calculus? I'm a mathematician and this is similar to one way to define integers, so I may be filling in blanks that aren't there. Then they try to show equality between numbers (which doesn't exactly work "because Lisp") by showing that the two functions generated by this process are equal... of course they are! You started with two numbers which were already equal, this isn't a proof of anything! Basically this gave me no insight into lambda calculus but I learned a couple of lisp functions.