A common internet trope we hear all the time is, “Well, I’m not convinced,” or “That doesn’t persuade me,” or “That doesn’t sound true to me.” And a lot of people get tripped up by this, because they think their job now is to sell the person on the truth of their position. But that already grants too much. We need to distinguish between the psychology of evidence and the epistemology of evidence. The psychology of evidence has to do with how evidence feels to you. Whether it moves you. Whether it strikes you as persuasive. Whether it produces some internal sense of certainty. But the epistemology of evidence has to do with whether the evidence actually supports the claim. Those are not the same thing. Merely reporting your psychological state might be interesting. It might tell us something about your background, your biases, your assumptions, your social environment, or your emotional resistance to a conclusion. But by itself, it has no philosophical weight. The question is not, “Am I convinced?” The question is, “What should convince me?” Notice how much work the word should is doing there. “Should” means we are no longer treating our private psychology as the standard. We are now submitting ourselves to a rule, a norm, a guideline, or an authority outside of our immediate feelings. And in this case, the authority is reason. Because none of us are ideal observers. There is no situation where two human beings are reasoning from a perfectly neutral, bias-free standpoint. We all come with emotions, desires, fears, incentives, background assumptions, biological pressures, and psychological complexity. So the point of reason is not that it magically makes us unbiased. The point of reason is that it gives us a way to regulate our biases. It gives us a standard by which we can discipline our psychology, rather than letting our psychology sit on the throne and call itself rationality. And this is where the epistemology of evidence matters. In philosophy, evidence is not just “whatever makes me feel persuaded.” Evidence is a relation of support. One proposition is evidence for another proposition when it raises, supports, or increases the probability of that proposition being true.