Anybody else love Logic?

[Bobby_T]

I can't get enough of the stuff.

and, or, exclusive or, conditionals, biconditionals, implication reduction, tautologies, contradictions and DeMorgan's Theorem.

Anyone know of what I speak? Any fellow logicians?

"If there are fellow logicians and they post here, then I will be happy"

or equivalently

"It is not the case that there are fellow logicians and they post here, or I will be happy."

First one to say which rule of inference I used wins a prize!

[Goat]

contradiction

[Bobby_T]

sorry that isn't an inference rule.

But here is an example of a contradiction

"I am taller than 10 feet and I'm shorter than 8 feet"

Simple isn't it?

[Bobby_T]

ok here's a hint. The list of implicational inference rules are:

p implies q
p therefore q (Modes ponens)

p implies q
not q therefore not p (Modes tollens)

p implies q
q implies r therefore p implies r (Hypothetical syllogism)

p implies q
r implies s
p or r therefore q or s (Constructive dilemma)

p and q therefore q (Simplification)

p
q therefore p and q (Conjunction)

p or q
not p therefore q (Disjunctive syllogism)

p therefore p or q (Addition)

Some equivalence forms are:

p implies q = not q implies not p (Contraposition)

not p and not q = not(p or q)
not(p and q) = not p or not q (DeMorgan's)

p implies q = not p or q (Implication reduction)

(p and q) implies r = p implies (q implies r) (Exportation)

and the list goes on ..
.
.
..
.
..
.

[{dC!}]

Im confused :(

[mapleleaf4ever]

The only logic that I'm good at is AND, OR, XOR, NOR, XNOR etc... TTL, CMOS... all that good stuff.

[{dC!}]

Logic is soO much broader then I thought!

[Courtney]

uhhh?
F Logic

[Bobby_T]

Originally Posted by mapleleaf4ever

The only logic that I'm good at is AND, OR, XOR, NOR, XNOR etc... TTL, CMOS... all that good stuff.

thats a good start.

[Grapes]

Implication reduction

I used to really like this stuff too.

The prof I learned it from at UBC sounded exactly like Nicholas Cage. Me and my friend spent half the term trying to figure out where we'd heard that voice before.

[Bobby_T]

Originally Posted by Grapes

I used to really like this stuff too.

The prof I learned it from at UBC sounded exactly like Nicholas Cage. Me and my friend spent half the term trying to figure out where we'd heard that voice before.

We have a winner!

1) If there are fellow logicians and they post, then I'm happy
2) Grapes is a fellow logician and he posted

Therefore I am happy....yay!

[pbreak]

What about falacies damn it!!

My logic course was tought by some 95 year old who I swear was already dead and somehow his after death twitching was moving him around and teaching us... thus I learned barely anything. I probably even spelled falacy wrong, but then again... maybe not.

[Grapes]

My logic course was tought by some 95 year old who I swear was already dead and somehow his after death twitching was moving him around and teaching us...

This is hilarious, therefore, I am loling.

I'm pretty sure I had profs like that!

Bobby T, my prize had better be cold hard cash.

[stringbeans]

yeah i did this at bcit.. discreet math!

[interloper]

Logic is by far the easiest section of Discrete Mathematics at SFU (macm 101). I loved doing it.

-Preet

[ebbomega]

Interloper: No way! Once you grok your head around Induction I'd say that's the easiest part.

Course, I had Brad Bart teach me and he fucking ruled. And it takes you a while to grok induction.

P(k)^(P(n)->P(n+1))=>P(x) | x >=k

edit: Smilies + Math = BOO!

[interloper]

I had Bart as a teacher aswell. Induction was by far the best part of Macm 101... soooo easy, but logic was easy as well, but it tickled your mind just enough.

-Preet

[galaxie]

Geeks!!!! :p