This is one of the great disconnects between computer scientists and biologists. Computers are man-made, and fundamentally knowable - answers will be definitively, provably, right or wrong.

Biology is different. Sure, at a molecule level, you can make definite conclusions. "This drug binds to that receptor."

But the kind of biology that is immediately useful to humans - where it touches on psychology or sociology - is too complex to get 100% right. So how do you do 'science' in these fields?

The answer is that you make up some cohesive theory based on existing research and do studies in that direction. You try to prove yourself right.

And it works! Theories that come out of this sort of research can turn out to be 100% true. Or 90% true - where they are wrong under some conditions, but still very useful. Or they can be complete bunk - not predictive, and a waste of time.

When anyone presents a cohesive theory of a complex system, they are probably not 100% right. Doesn't make them entirely wrong, though, and certainly not useless.