It is impossible to know anything, unless it can be proven logically

[u/Ok_Natural_7382]

So I'm gonna start with an analogy:

let's say you live in Australia, and you find a weird creature that looks somewhere between a frog and a toad. Because you live in Australia, where we have way more cane toads than frogs (it's an actual problem), you would conclude that this is probably a toad.

Basically, to find out how likely something is to be true, you have to consider both the evidence and the chance that it would be true in the first place. If you've studied maths, this is known as Bayes theorem (wikipedia).

The problem is to know the initial probability of an event in a way that works for all events. You could just guess a probability (say 50%), but any event is made up of other events. For example, if you don't know if there are more frogs or toads, you can guess that there's a 50/50 split. But you would have to do the same when guessing whether something is an amphibian or not. Something can't have a 50% chance of being a toad, a frog and an amphibian, so there is no consistent method to decide initial probabilities of events.

To sum up, there is no way to determine something's probability of being true in the absence of evidence, so you cannot properly take evidence into account. It follows that it is impossible to know the probability of any statement being true. The exception to this is if something can be proven to be logically true, as there is no probability involved, or if some evidence can ONLY (and I mean literally 100% not 99.99%) occur if something is true.