It&#x27;s logically impossible for proof to exist, but I think observation and comparison count as evidence. For example, if I see your signature on a document, that&#x27;s evidence that you signed it, even though I can&#x27;t prove that it&#x27;s not forged. Similarly, if I see you act distressed after touching a hot stove, that&#x27;s evidence that you felt pain, even though I can&#x27;t prove it.<p>The only thing you need to take on faith is that your perception of the world is not simulated. Assuming that your experiences are real, every comparison of yourself to other people is evidence that you work the same. You can compare behavior, MRIs, xrays, whatever.