I actually love RPN, but that's only since I've seen it explained a certain way, I think it was in a manual on the Forth language. RPN makes sense for a computer, because you first give it all the information it needs to do something with, and only then what to do with it. Doing it the "classic" way (3+5) makes much less sense, because you tell the computer: here's a bit of incomplete info (3), please perform this operation (+), and oh here's the rest of the info (5).

It also said that it's in a way closer to how humans think: I have two numbers, and I want to add them up.

For me it also helps to think that RPN is based on a stack. In "3 5 +", 3 and 5 are pushed onto a stack, and + pulls two numbers off the stack, adds them up and pushes the result (8) back on the stack.