is good in relation to a certain kind. For example, a person with a clear voice may be a good singer or a knife with a blunt edge may be a bad knife. But this still leaves it open whether the entity in question is good or bad in an unqualified or predicative sense. For example, a person may be a bad assassin but being bad as an assassin is not bad in a predicative sense. Axiology is usually interested in the predicative sense of goodness. But some philosophers deny that such a sense exists and therefore hold that all value is relative to a kind. A second important distinction is that between being good for a person and being good for the world. Being good for a person or prudential value has to do with this person's welfare or well-being. But what is good for one person may be bad for another person. For example, having a dry summer may be good for the hiker in virtue of the pleasant hiking conditions, but bad for the farmer, whose crop is dying because of a lack of water. In such cases, the question arises as to what is good for the world or good simpliciter. Utilitarians can solve this problem by defining the good for the world as the sum of the good for each persons. Philosophers often distinguish between evaluative concepts (like good or bad) and deontic concepts (like right, fitting or ought). The former belong to axiology proper and express what has worth or value while the latter belong to ethics (and related fields) and express what one ought to do. Philosophers have tried to provide a unified account of these two fields since they seem to be intimately related. Consequentialists see evaluative concepts as fundamental and define deontic concepts in terms of evaluative concepts. Fitting-attitude theories, on the other hand, try to reduce evaluative concepts to deontic concepts. Consequentialism is an ethical theory that holds that, given a certain set of possible actions, we ought to perform the action that has the best overall consequences. So what we ought to do is defined in evaluative terms: whatever leads to the consequences with the highest value. Fitting-attitude theories are axiological theories that define the value of something in terms of the attitude that would be fitting to have towards this thing, for example, that it would be good