One of the issues raised At the moment, is epistemology of value propositions. From viewpoint of some, value concepts are of philosophical concepts, And at result, propositions emerged from these concepts, are increasing-knowledg and provable. And from viewpoint of some, Concepts of this propositions, are from credibility of mind and since that the matter of analogy is from credits of mind, as a result propositions emerged from these concepts, he does not give, knowledg and are indemonstrable. Another argument that will proposed after this view, is the relative of value propositions. This treatise will that with a view of problem-oriented, with description and comparison between of writing of these two noble and rational analysis them, reality, would become clear. From accuracy in their writings, it shows that Allama and the martyr Motahhari, beliefs the second theory. But relativity of value propositions can not be attributed to them. It seems that view of credit is correct, in non-declarative sentences, but in the declarative sentences is not correct. Many defects, entered on ideas of Allama and martyr Motahari but most of them are not correct.