Philosophy - #2, 3 and 4 (and #6)

Braintwisters #2, 3 and 4 are essentially variations of the following paradox:

1) Statement 2 is true.
2) Statement 1 is false.

If 1 is true, then 2 is true. But if 2 is true, then 1 is false. But if 1 is false, then 2 is false. But if 2 is false, then 1 is true...

It's just wordplay; there's no solution.

#6, though different, is lumped in with this post because both explanations are short. It assumes that the donkey would be caught indefinitely due to never being able to make a rational decision between two equal things. But guys (and gals), in the real world, there's no "perfectly equal" scenario. Maybe the wind blows from the west. The donkey sniffs the food coming from that direction a little stronger than it does the food-smells from the east, so it heads west. Maybe a fly itches the donkey's neck, and it moves its head to the right. Since it's already looking to the right, it ambles in that direction. There will always be some little disturbance that tilts the balance one way or another. Sort of like how an inverted pendulum will never balance upside-down, even though there's an equilibrium position in that arrangement. Mathematically it's fine, but physically it won't work.