My favourite is this:
If you randomly guess at this multiple choice question what are the odds you get it right?
a) 25%
b) 50%
c) 25%
d) 0%
The Pogo Paradox. Where an event is caused by the very attempts to prevent it.
This sentence is false
Time is relative, especially to speed. If somehow I go at light speed into space and relax for 24 hours then return at light speed it’d be the future. Fucking Interstellar.
Zeno’s paradox of motion. If you shoot an arrow at a target, at some point it’s halfway there, then halfway of the remaining half, etc. Since no remaining distance cut in half can ever equal zero, the arrow never reaches the target.