Abstract
Suppose you perceive a ball’s redness, and on that basis come to believe that the ball is red. Is it necessary that, if you have the basis that you do have for your belief, then your belief is true? In other words, is your belief conclusively based? After motivating the project of answering this question in the affirmative, I argue that the traditional positive relationalist answer (given, in importantly different ways, by Johnston, Schellenberg, and on at least some readings, McDowell) fails, because it entails (falsely!) that a ball’s yellowness and a ball's redness cannot both be successfully perceived yet appear the same to the perceiver. I then develop an alternative positive relationalist answer to the conclusive basis question, which is free of the false entailment.