How they prove that all odd integers higher than 2 are prime? Math Educator: 3 is a prime, 5 is a prime, 7 is a prime, and by induction  every odd integer higher than 2 is a prime. Physicist: 3 is a prime, 5 is a prime, 7 is a prime, 9 is an experimental error, 11 is a prime,... Engineer: 3 is a prime, 5 is a prime, 7 is a prime, 9 is a prime, 11 is a prime,... Programmer: 3 is a prime, 5 is a prime, 7 is a prime, 7 is a prime, 7 is a prime,... Salesperson: 3 is a prime, 5 is a prime, 7 is a prime, 9  we'll do for you the best we can,... Computer Software Salesperson: 3 is prime, 5 is prime, 7 is prime, 9 will be prime in the next release,... Biologist: 3 is a prime, 5 is a prime, 7 is a prime, 9  results have not arrived yet,... Advertiser: 3 is a prime, 5 is a prime, 7 is a prime, 11 is a prime,... Lawyer: 3 is a prime, 5 is a prime, 7 is a prime, 9  there is not enough evidence to prove that it is not a prime,... Accountant: 3 is prime, 5 is prime, 7 is prime, 9 is prime, deducing 10% tax and 5% other obligations. Statistician: Let's try several randomly chosen numbers: 17 is a prime, 23 is a prime, 11 is a prime... Professor: 3 is prime, 5 is prime, 7 is prime, and the rest are left as an exercise for the student. Computational linguist: 3 is an odd prime, 5 is an odd prime, 7 is an odd prime, 9 is a very odd prime,... Psychologist: 3 is a prime, 5 is a prime, 7 is a prime, 9 is a prime but tries to suppress it,... There are two groups of people in the world: Those who can be categorized into one of two groups of people, and those who can't.  
The Flood is over and the ark has landed. Noah lets all the animals out and says, "Go forth and multiply." A few months later, Noah decides to take a stroll and see how the animals are doing. Everywhere he looks he finds baby animals. Everyone is doing fine except for one pair of little snakes. "What's the problem?" says Noah. "Cut down some trees and let us live there", say the snakes. Noah follows their advice. Several more weeks pass. Noah checks on the snakes again. Lots of little snakes, everybody is happy. Noah asks, "Want to tell me how the trees helped?" "Certainly", say the snakes. "We're adders, so we need logs to multiply. Two statisticians were traveling in an airplane from LA to New York. About an hour into the flight, the pilot announced that they had lost an engine, but don't worry, there are three left. However, instead of 5 hours it would take 7 hours to get to New York. A little later, he announced that a second engine failed, and they still had two left, but it would take 10 hours to get to New York. Somewhat later, the pilot again came on the intercom and announced that a third engine had died. Never fear, he announced, because the plane could fly on a single engine. However, it would now take 18 hours to get to New York. At this point, one statistician turned to the other and said, "Gee, I hope we don't lose that last engine, or we'll be up here forever!"  
 Why did the chicken cross the Möbius strip? To get to the same side

2b or not 2b that is the answer.  
A mathematician went insane and believed that he was the differentiation operator. His friends had him placed in a mental hospital until he got better. All day he would go around frightening the other patients by staring at them and saying "I differentiate you!" One day he met a new patient; and true to form he stared at him and said "I differentiate you!", but for once, his victim's expression didn't change. Surprised, the mathematician marshalled his energies, stared fiercely at the new patient and said loudly "I differentiate you!", but still the other man had no reaction. Finally, in frustration, the mathematician screamed out "I DIFFERENTIATE YOU!" The new patient calmly looked up and said, "You can differentiate me all you like: I'm e to the x."  A biologist, a statistician, a mathematician and a computer scientist are on a photosafari in africa. They drive out on the savannah in their jeep, stop and scout the horizon with their binoculars. The biologist: "Look! There's a herd of zebras! And there, in the middle : A white zebra! It's fantastic! There are white zebras! We'll be famous!" The statistician: "It's not significant. We only know there's one white zebra." The mathematician: "Actually, we only know there exists a zebra, which is white on one side." The computer scientist: "Oh, no! A special case!" 
An Engineer, a Physicist, and a Mathematician are shown a pasture with a herd of sheep, and told to put them inside the smallest possible amount of fence. The Engineer is first. He herds the sheep into a circle and then puts the fence around them, declaring "A circle will use the least fence for a given area, so this is the best solution."
The Physicist is next. She creates a circular fence of infinite radius around the sheep, and then draws the fence tight around the herd, declaring "This will give the smallest circular fence around the herd."
The Mathematician is last. After giving the problem a little thought, he puts a small fence around himself and then declares, "Let the area where I am standing be defined as the outside." 