Tag Archives: logic

U Can’t Prove This


So in celebration of this, I wrote a song.

It’s sung to the tune of—of course—M.C. Hammer’s U Can’t Touch This.

Oh, and Dr. O’Rourke, if you EVER happen upon this for some reason, I want you to know that this is totally proof (ha! Get it?) that your class had an impact on me and that I loved it. This is dedicated to all of us who, for some reason or another, take a long time to wrap our heads around proofs. Where the free time to write this drivel comes from, I will never know.


“U Can’t Prove This”

U can’t prove this
U can’t prove this
U can’t prove this
U can’t prove this

My, my, my, Symbolic Logic, it’s so hard
Makes me say oh my Lord
It seems okay when you’re doing truth tables,
Translations, worlds, you feel quite able
But then you get to problem set four
Crap like you’ve never seen before
Gone are the days of logic bliss
You throw up your hands and say, “u can’t prove this”

I told you, freshman, u can’t prove this
Yeah that’s how we’re graded and you know, u can’t prove this
Look at this statement man, u can’t prove this

Yo let me bust the logic lyrics, u can’t prove this

Boole and Tarsky, Wittgenstein
You start missin’ these guys when you enter the land
Of proofs, it’s quite sad
Who knew philosophy could kick your ass?
Can’t prove a thing without some guidance
Wish you’d taken computer science
But now you’re stuck
You know this class is gonna test your luck
Make it known you can’t get the groove

That this is a statement you can’t prove

Yo I told you, u can’t prove this
Why you standing there man, u can’t prove this
Yo sharpen your pencil, logic class is startin’, u can’t prove this

Then you start to understand
The relief you feel is oh, so grand
But then Prof says, “oh there’s more”
Gives new rules, subproofs galore
And now you’re screwed
Just when you thought your struggle was subdued

You’ve got this “if, then…”
So you go through the pain all over again
Assume P, or not P?
Who the hell knows, it’s all Greek to me

It’s hard because you know
U can’t prove this
U can’t prove this
Break it down!

Stop. Logic time. 

Go with the flowchart it is said
If you can’t prove the former than you’re probably gonna dread
These quants—they’re real tough

You’re trying to learn more but you’ve had enough
Of these rules—they’re absurd
What do they expect, you’re no logic nerd
Backwards E’s and upturned A’s
Out the window flies your grade

A, B, C, D, F, yeah, u can’t prove this
Look man, u can’t prove this
You’d better do the extra credit, boy, ‘cause you know you can’t prove this

Ring the bell, it’s logic time, break it down!

Stop. Logic time.

U can’t prove this
U can’t prove this
U can’t prove this

Break it down!

Stop. Logic time.

Every time they see you, you’re working on these proofs
You’re hunting like a bloodhound, a modus pollens sleuth

Now how could you ever increase your proving speed
When you can’t seem to prove concisely what you need
You’ve done so much already, there’s so much more to do
It’s subproof new subproof ‘nother subproof twelve subproofs and you’re hardly half way through

U can’t prove this
U can’t prove this
U can’t prove this
Yeah, u can’t prove this
I told you, u can’t prove this
Too hard can’t prove this

Get me outta here, I can’t prove this

People underestimate the genius of Weird Al. This is hard. And it doesn’t help that this song is like five minutes long.


Guys, there is a best of all possible worlds, and this is what it looks like:

This is from Tarsky’s World, my Symbolic Logic’s virtual world where we can validate/invalidate sentences. Today I (barely) started working on my logic homework. So I get to this one problem and read this: Launch Tarsky’s World and open Leibniz’ World

Of course, if you have been listening to me at all these past few weeks, you can imagine the ruckus this caused. Well actually, it caused virtually no ruckus, as I was in the recitation session at the time so I couldn’t jump up and down and scream “HOLY CRAP!” like I wanted to. So I just sat there giggling to myself and reveling in my little joke for about ten minutes.
Seriously guys. Leibniz claims there is a “best of all possible worlds.” There is a Leibniz’ World in LPL’s files. I have got to think the writers of Tarsky’s World had to understand the little joke they made. This is almost better than the cookies.

Haha, I’m sorry, this is probably a really boring blog, but it’s funny as hell to me.

The Leibniz jokes will subside in due time, perhaps after I get my chocolates in the mail, or perhaps after I read some of his other writings. But as of now, you guys’ll just have to deal with them. At least I’ve refrained from the statistics jokes for awhile, right?

Halfway through, still holding strong…

HA! Spring Break, baby! I didn’t think I was going to make it past this week…Monday-Thursday was incredibly stressful. But here I am, at the midpoint of a semester of 25 credits, and holding a 4.0 so far (with 4 out of 9 classes reporting). And the real surprising thing is the fact that I’m holding up surprisingly well. Haven’t crumpled under the stress yet (though I was close on Tuesday, not going to lie). I think I’ve hit my stride with this workload. Unfortunately, I’m very tempted to increase my credit load in the fall to something like 27, but I won’t do that. It’s silly and unnecessary, especially if 6 of my credits next semester are going to be coming from graduate-level statistics classes (which, if they’re both offered, will be the case). I just hope the 4.0 can last until the end of the semester…please, oh please…

Hmm…what else was I going to say in this thing today…

Oh yes! I was going to give you guys an example of a formal proof. This was one of our practice problems, one full of those delicious things we call subproofs! Observe (oh, and the little carat (^) is read as “and,” the little v is read as “or,” that little tilde-like thing at the beginning of the first premise is read as “not,” and _|_ is the symbol for a contradiction. Like that will help at all, but just thought you should know):

Oh, and the goal is to prove R.

This was done in Fitch, the program we use. It’s picky as hell. “Fitch” does not rhyme with “bitch” for no reason, as one person pointed out in our recitation session.

Oh, and an album cover! I like putting wings on things. I’d show you the original, but I’ve lost it (not it it, the picture, it…aw, nevermind).