Do crazy people exist?

hort answer: Yes, but it depends entirely on which definition you’re using.

Since “crazy” isn’t an official medical term, here is how those people exist in the real world:

• Clinically (Severe Mental Illness & Psychosis): People whose brains process reality in ways completely disconnected from the rest of us—hearing voices, experiencing unshakeable delusions, or losing touch with rational thought—definitely exist. Today, medicine categorizes this as severe psychiatric illness, psychosis, or neurodivergence rather than “craziness.”
• Legally (“Insanity”): “Insane” exists as a legal standard, referring to someone who, due to a severe mental disorder, cannot comprehend the nature of their actions or tell right from wrong at the time of a crime.
• Socially / Colloquially: People who display extreme recklessness, total disregard for social rules, or wild unpredictability exist everywhere. We often call them “crazy,” though that’s just informal slang.

Bottom Line: If you mean “do people exist whose minds or actions seem completely irrational and ungrounded to everyone else?”—yes, absolutely. Science just uses more precise terms for it today.

Are you asking from a psychiatric angle, a historical one, or are you thinking about a specific type of behavior?