  Why think that 3 is not evidence for 1? Kelly (2005) cites several reasons. First, when people cite their justification for their beliefs, they do not typically cite things like 3. We typically treat the fact that someone believes a proposition as the result of the evidence for that proposition, not as another piece of evidence for that proposition. Second, since people form beliefs on the basis of a body of evidence, to count their belief as yet another piece of evidence would amount to double-counting that original body of evidence. On this line of thought, one’s belief that \(P\) serves as something like a place-holder for the evidence upon which one formed the belief. So, to count both the belief and the original evidence would be to double-count the original evidence, and double-counting is not a legitimate way of counting.