If you switched on the light this morning and walked to the bathroom, you've put yourself in the middle of a philosophical conundrum. In one case, you have accomplished what's known as a supertask. In the other case, you've done something that shows supertasks are impossible.
Zeno of Elea was a Greek philosopher who suggested that if you could slice time into small enough increments, the world would freeze in place. It turns out that he was right — at least, from a quantum mechanics perspective.