A mathematician, an engineer and a priest are trapped on the 10th floor of a hotel on fire. Their only chance of escaping is jumping into a tiny pool.

"If it's God's will, I'll be saved" says the priest. He jumps and lands right into the middle of the pool.

The engineer takes some measurements, makes some calculations, builds a lever out of a closet door and throws himself right in the middle of the pool.

The mathematician makes lengthy calculations, jumps out and starts floating upwards. "Damn! I must have gotten a sign wrong somewhere." he thinks.

What's red and invisible?










No tomatoes.

My three favourite things are...
Eating my kittens and not using commas.

So, one of them approaches the woman, talks to her, and she says, "Sorry, you flatter me, but I'm not gay!".

[Serious mode]
Actually, the mathematical answer is that they will get to the woman in a finite amount of time. While it takes an infinite number of steps, each step takes less time than the previous one, and the size of the steps converges to 2.
[/Serious mode]

Here's another joke (don't know if I posted it before):
A train is about to run over some people, but there is a switch to make it take a different path.
If the switch is not pressed, the train will run over 1 + 1 + 1 + 1 + ... people, which diverges and is therefore infinite.
If the switch is pressed, the train will run over 1 + 2 + 4 + 8 + ... people, which via analytic continuation, sums to -1 people.
Should the switch be pressed?

(If you don't believe the part about the switch being pressed, just use the formula for the sum of an infinite geometric series, and ignore the pesky rule saying it only applies if abs(r) < 1. Notice that this only gives you a finite answer in the second case.)

Let's eat Grandpa!

You mean Robert Gates, right?

A linguistics professor says during a lecture that,

“In English, a double negative forms a positive. But in some languages, such as Russian, a double negative is still a negative. However, in no language in the world can a double positive form a negative.”

But then a voice from the back of the room piped up,

“Yeah, right.”

If you ever get locked out of your apartment, do not panic. Take a deep breath, relax and talk to the lock calmly...

Because communication is key.

In English, "i" comes before "e", except after "c".

Isn't that wierd?

I was going to post that, but you beat me to it. Assuming a constant speed, the time taken is finite. Assuming time taken to cover the first half is 1 unit, total time is

1 + 1/2 + 1/4 + 1/8 + ... = 2

Consider this: you throw a ball that is 1m away from a wall with a constant speed of 1 m/s. Assume a "step" is taken each time the ball covers half the remaining distance.
a) How many "steps" did the ball take before it hits the wall? Infinite.
b) How much time did the ball need to hit the wall? 1s.

Similarly, as I pointed out in the next post, 1 + 2 + 4 + 8 + ... = -1, right?

Me: "Hi, I'm here for the Paradox Club."

Response: "Actually, this is the Oxymoron Club."

Me: "Okay, same difference."
*looks at group*

Response: "Oh, this guy is good."

^ This guy is good.

Here's a version of one of my favorites:

The below statement is false.
The above statement is true.

It also works if calculated on a 32bit computer and you stop ar running over
1 + 2 + 4 + 8 + ... + 1073741824 people.

Although its hard to find people that find two's complement integer overflow jokes funny.

In classical (Newtonian) physics, we can't solve the three-body problem.
In the theory of relativity, we can't solve the two-body problem.
In quantum mechanics, we can't solve the one-body problem, and with
quantum electrodynamics, we don't even understand the vacuum anymore.