Abstract
This paper challenges some leading views about the conditions under which the ascription of beliefs and desires can make sense of, or provide reasons for, a creature's behavior. I argue that it is unnecessary for behavior to proceed from beliefs and desires according to the principles of logic and decision theory, or even from principles that generally get things right. I also deny that it is necessary for behavior to proceed from principles that, though perhaps subrational, are similar to those that we ourselves use. I then propose some conditions that are considerably weaker, and argue that they fulfill the descriptive and explanatory requirements of intentional ascription