 The most common versions of anti-doxastic arguments seem to rely on an idealization of belief states, and impose constraints on delusions that not even typical beliefs would meet. The assumption seems to be that beliefs are essentially rational, and that delusions are not beliefs because they are not rational. But the abundant psychological evidence on familiar irrationality tells us that nondelusional beliefs are often irrational in exactly the same way as delusions can be, although to a lesser degree. It is sufficient to think about hypocrisy, about prejudiced and superstitious beliefs, and about the many biases that affect belief updating in normal cognition to realize that the same kinds of irrationality that we find in delusions are also common in many nondelusional beliefs (e.g., Nisbett and Ross 1980; more recently Bentall 2018). A general worry is that the very notion of belief is not theoretically useful if the criteria for what counts as a belief become too loose.