To oversimplify, it’s a metaphor about what it’s like to go through life relying only on your senses and not using reason to question or analyze the deeper meanings behind your surface impressions. The story goes on to discuss a prisoner who escapes the cave and gets a taste of true reality, that prisoner is meant to represent a philosopher. When the escaped prisoner returns and tells the others of what he’s seen, they reject his claims saying how absurd it would be to believe that there’s anything more than just the shadows. I think in this day and age it’s easy to guess what that interaction represents, but Plato had a particular bone to pick about this since his mentor had essentially been executed for questioning various things.

https://en.wikipedia.org/wiki/Allegory_of_the_cave?wprov=sfla1

Holy crap. This should be it’s own post. Just purged all the “serious” communities I was following on there.