A mathematician, a physicist, a civil engineer,
and a computer programmer are asked (after a few beers) to show
that all odd numbers greater than 1 are prime.
mathematician: 3 is prime, 5 is prime, by induction they're all prime.
physicist: 3 is prime, 5 is prime, 7 is prime, 9 is... experimental error, 11 is prime, 13 is prime -- clearly, they're all prime.
civil engineer: 3 is prime, 5 is prime 7 is prime, 9 is prime, 11 is prime -- sure, they're all prime.
programmer: 3 is prime, 5 is prime, 7 is prime, 7 is prime, 7 is prime, 7 is prime, 7 is prime......