Science is about what you can disprove, not what you can prove.
In order for a general theory to be scientific, it must be amenable to the scientific method. This means that it must generate hypotheses which could hypothetically prove that the theory is false, IF IT TRULY IS FALSE.
Google the term falsificationism and popper and ignore any nonsense you find on a creationism or ID site, because they get it wrong. The evolutionists get it right, but ignore them too. Instead, try to get it from a philosophy of science site.
(And not some religious site masquerading as a science site.)
No amount of evidence can prove that a general theory is true - which is to say that no amount of evidence can prove induction. (Bear in mind that what you might have learned as "method of induction" in algebra really isn't induction - try not to get confused here. I know the terms are a little messed up.)
Example, no matter how many times you see a crow that turns out to be black, that does not disprove the existence of white crows. However, the existence of only black crows is not really a theory with a lot of predictive power. That theory is too specific.
However, there are theories that are pretty general. For example, the theory of gravity (not to be confused with the fact of gravity) is pretty general. We can easily generate hypotheses from this theory that might disprove it, if it weren't true.
