## Search found 6 matches

- Sat Jan 05, 2008 4:08 am UTC
- Forum: Computer Science
- Topic: Abstraction elimination
- Replies:
**0** - Views:
**2156**

### Abstraction elimination

I am currently trying to write stuff (yes, stuff) in a sort-of lazy Unlambda. To make things easier, I wrote a small abstraction elimination program (The Abstractor, informally), here included : http://membres.lycos.fr/bewulf/Russell/AE6.py Most functions (I think the ones withoutn lambdas in them) ...

- Tue Dec 25, 2007 8:29 pm UTC
- Forum: Computer Science
- Topic: Pred. function, lambda calculus
- Replies:
**3** - Views:
**3054**

### Re: Pred. function, lambda calculus

Well, that would explain it. Thanks.

- Mon Dec 24, 2007 12:07 am UTC
- Forum: Computer Science
- Topic: Pred. function, lambda calculus
- Replies:
**3** - Views:
**3054**

### Pred. function, lambda calculus

I tried some Lambda expressions, and got this. I also tried without changing the variables name (the ij ones), but I didn't get anywhere good. Can someone tell me what I'm doing wrong?

- Wed Oct 10, 2007 6:45 pm UTC
- Forum: Mathematics
- Topic: Favorite Mathematical Equation
- Replies:
**87** - Views:
**21707**

### Re: Favorite Mathematical Equation

I like the Meredith axiom. ((((p->q) -> (~r->~s)) -> r) -> t) -> ((t->p) -> (s->p)) You can derive any true formula with this axiom, substitution and modus ponens (well, at least in the context of classical propositional logic). And it just might be the shortest way to do it!

- Wed Sep 19, 2007 8:17 pm UTC
- Forum: Mathematics
- Topic: Basic/Self-Evident Truth in Mathematics
- Replies:
**53** - Views:
**11984**

Also NBG set theory, which introduces the concept of a proper class thus avoiding Russell's paradox, and I believe there are one or two other reasonably well-known alternatives. NBG is as far as I know pretty much ZFC with the notion of proper class. It's the system used on Metamath. The only novel...

- Wed Sep 19, 2007 11:12 am UTC
- Forum: Mathematics
- Topic: Basic/Self-Evident Truth in Mathematics
- Replies:
**53** - Views:
**11984**