Thought Experiments

What are they good for?

Ever tried making a thought experiment?

Join us in the main lounge on Monday at 10:15 PM and share it with Philosophy Section. In the mean time, try to wrap your head around these.

Hilbert's Hotel

Suppose you visit a hotel with infinitely many rooms. You check-in and see that the guest checklist reads "full" in bold letters. As you begin to leave, the manager rushes to tell you that you are surely going to get a room. He sends an email to each guest to tell them to move to the room two doors up from them (1 to 3, 2 to 4, and so on). The manager, smiling, tells you you may now have your choice of infinitely many rooms, and that everyone else is accounted for.

Mary's Room

Mary has lived in a black and white room all her life, and she has never seen any colors. She is a genius, however, and has learned every fact possible about physics, biology and the brain. One day, Mary leaves her room, and sees color for the first time. Has she learned anything new?

Lucretius' Spear

Suppose you go to the edge of the universe and hurl a spear. If it goes on forever, the universe does too. If it hits a wall, then what's behind the wall? Surely more universe, so either way, the universe is infinite, right?