Solipsism is the idea that only your mind exists. Everything else — other people, the external world, this sentence you’re reading — might be fake.

It sounds crazy. But here’s the logic.

You only have direct access to your own thoughts and experiences. Everything else comes through your senses. But senses can be fooled. Dreams feel real while you’re dreaming. Hallucinations seem genuine to the person having them.

So how do you know other minds exist? You see bodies that act like they have minds, but you never experience someone else’s consciousness directly. Maybe they’re just sophisticated robots. Or maybe your brain is generating the whole show.

The philosopher who took this furthest was probably Descartes, though he didn’t stay there. He said the only thing he could be certain of was his own thinking. Everything else was doubtable.

Most philosophers think solipsism is wrong but hard to refute completely. You can’t prove other minds exist the way you prove mathematical theorems.

The weird thing is that solipsism might be the most logical position and also completely useless. Even if other people are figments of your imagination, you still have to live as if they’re real. The imaginary people still seem to suffer when hurt.

And if you’re wrong about solipsism, you’ve just been treating real conscious beings like they don’t matter.

So maybe the question isn’t whether solipsism is true. Maybe it’s whether believing it would make your life better or worse.

I think I know the answer to that one.

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