Is it possible that my current reality isn't real at all?
Plato's allegory of the cave from his book "The Republic" describes the problems with understanding and interpreting reality.
Does questioning the nature of reality make you an insightful genius, or just insane?
Plato wants us to question the very nature of the reality we can see - recognizing that we are limited by our experiences and our natural abilities - and imagine that there might be something more; something we are incapable of understanding simply through direct observation.
Consider that in the past, and likely now, people have often confused what the world seemed to be with what the world really was.
The world is flat and at the center of the universe.
Mercury and lead are good for you.
Heroin and cigarettes could keep you healthy.
Time will tell what the future thinks we were crazy to believe.
How do I know what I know?
Epistemology: the philosophical study of knowledge.
Skeptic: a skeptic is someone who questions whether it’s possible to know anything with certainty.