it is well known that kant applies the concept of "analogy" many times in many different contexts. the literature does not take into account, however, a peculiar and implicite use of analogy kant makes in his writings, which seems to be essential to the appraisal of human actions. the present paper maintains that we can only understand and apply the principles of moral and law to impute actions if we presuppose a certain analogy between us and the others, between our capacities, rights and duties, and the capacities, rights and duties we suppose other people do have, as well as between the different political states and systems of law and ours. thus, in the first part of the paper i analize many different passages and contexts in which kant uses the concept of analogy, in order to track and make clear the general notion kant implicitly applies. in the second part i apply the results of the previous analysis to the moral point of view to show that the application of the categorical imperative as rational principle of internal legislation sets a problem to the imputation of actions which could only be solved by supposing an analogical knowledge of humans and their actions that the kantian theory cannot admit in this context. in the third part i concentrate in the appraisal of actions from the point of view of right and law by describing the universal principle of right as rational foundation of external law and duty, in order to show that its application presupposes not only the same analogical knowledge of humans and human actions, but also allows to solve the problem of imputation faced from the moral point of view. in the end i present a brief reflection on the significance of analogy as a rational principle for the evaluation of human action.