An Epistemological Study of Rational Good and Bad

The problem of human deed`s Goodness and badness is one basic problem in theology, usuli fiqh and ethics; it may be studied in different aspect of semantics, ontology and epistemology. Whether goodness and badness are essential to deeds or not is ontological; but whether it is rational or not, is epistemological. Often, these two aspects are not properly distinguished and it leads to some fallacies. This paper, having distinguished the two aspects, deciding the place of dispute and describing epistemological consequences, has argued for rationality of those propositions of goodness and badness by giving three proofs. Upon the first, if the goodness and badness are not rational, one may not be of any knowledge of the goodness of human deeds at all, even by way of religion. The second proof proves that these propositions carry certainty and, therefore, are used in the premises of logical demonstration; they are not among those known only as well-known used in dialectic. On the third reason, the validity of certain deeds is known as self-evident and, thereof, certain and rational. Although numerous epistemological objections have been given against the proofs, finally the paper, giving certain arguments, has defended rationality of the goodness and badness of these propositions