Greedy Son: Dad, I need some new clothes. Gimme some money. Strict Dad: How many money do you need [pulls out wad of bills] Greedy Son: Mind your own business! I don't tell you how to earn the money, so don't tell me how to spend it! I'll ask Mom instead. Lazy Mom : Here's a credit card, Son. Just charge what you need.
- Borrowing from the Future
Student: I need a list of prime numbers Teacher: Easy. I'll give you the first one: 2. Now test each odd integer starting at 3 and try dividing by every prime up to its square root. Student: But I need to already know the primes in order to divide them into my candidates, don't I? Teacher: No problem, I have an infinite list of them! I'll make you a deal. I'll feed you these divisor primes as you need them, and you tell me whether your numerator ended up being prime. Student: OK, 3 is the next prime number Teacher: [Quickly writes this down on his list] Student: Hey, you're cheating! I'm the one doing all the work here! I'm generating primes faster than I need them, so really I'm stealing from myself. What's the use pretending I'm getting them from you? Teacher: No, I'm just doodling, I really do know all the primes. Your code is much simpler with me handing you the divisor primes anyway. What do you care where I get them from? It's no extra work for you!
- Running in Circles
Athlete: I run on an infinitely long track. I can go forever in a straight line without coming to the end. Trainer: Dummy, you're running on a treadmill. Look around: the walls aren't even moving. Athlete: I can't, the lights are off. The only thing I can see is the lighted path at my feet. Trainer: Moron! Don't you see that number "2" painted on the treadmill that keeps repeating every couple meters? Athlete: Of course, amazing how someone had the patience to keep painting the number 2 over and over. Trainer: Has it occurred to you that that is the same number "2" going by each time? Athlete: Prove it! Trainer: Easy, I'll just write a "3" next to it. See, the "2" is gone, now it's "23". Athlete: Now who d'you think you're fooling? You just knew the numbers ahead were all "23" after a certain point. Trainer: You're unbelievable! Don't you remember that there were numbers "2" before, and now it's "23"? Athlete: That's what I'm saying! Trainer: Your logic is too lazy for me. You can't tell the difference between an infinite list and a cyclic one. Athlete: What do I care? I still get all the exercise I need!