system
Given the following post, respond as if you're commenting on Reddit:
human
[Marvel] How does Spider-Man's spider sense work as a spider-based power? Spiders aren't psychic.

As Spidey shows in the first Amazing Spider-Man, spiders can sense movement on webs. However, that's not how it works. Spider-Man seems to have precognition. Spiders don't have precognition, even radioactive or genetically engineered ones. So, what's up? How does spider sense work?
gpt
Spider-Man's powers aren't due to his body becoming more spider-like. For instance, a spider can climb on walls because it is lightweight and has many tiny, rough contact points that allow it to grip onto the imperfections in a surface. Spider-Man can climb walls because he can control the attraction between his molecules and those of whatever he touches, essentially bonding to them on an atomic level. (this has an interesting side effect-- no force on earth can make him let go of something if he doesn't want to, his arms will tear out of their sockets or the surface itself will break before his grip does.)

In short, it's probably just lucky coincidence (or the will of the spider-totem) that he got the powers he did and that they generally resemble abilities a spider has.