Try not to make decisions without the facts. Get the facts and spend time thinking over the problem.
Create a hypothesis— a yet-to-be-proven theory. Then seek ways to invalidate this hypothesis, to prove that your idea is wrong. This is what scientists do.
This is exactly the opposite of what most people do. They come up with an idea, and then they seek corroboration and proof that their idea is a good one. They practice “confirmation bias.” They only look for confirmation of the validity of the idea, and they simultaneously reject all input or information that is inconsistent with what they have already decided to believe.
Source: Get Smart – Farnam Street