Blame is described in Wikipedia as “the act of censuring, holding responsible, making negative statements about an individual or group that their action or actions are socially or morally irresponsible.” Praise, on the other hand, is said to be “the act of making positive statements about a person, object or idea, either in public or privately. Praise is typically, but not exclusively, earned relative to achievement and accomplishment.”
They may be opposites in that one is negative and the other positive but they share a common thread, which is that assigning blame or giving praise to someone both means assigning responsibility to that person. Because of this the very tricky issue of “free will” has to come into play, after all how can anyone be held responsible for anything without free will. And so the classic debate that is still as ever goes on.
If you are interested in delving more into the free will, blame, and praise issue a must read would be Garrath Williams’ article “Praise and Blame”. There he “contrasts three influential philosophical accounts of our everyday practices of praise and blame, in terms of how they might be justified” including the Kantian approach (where the subject of free will is discussed), the utilitarian approach (discusses praise and blame in relation to their usefulness in terms of social benefits), and the Aristotelian approach (focuses on mutual accountability and moral education).