The idea that we can properly be held responsible for what we believe underlies large stretches of our social and institutional life; without that idea in place, social and institutional life would be unthinkable, and more importantly, it would stumble and fall. At the same time, philosophers have argued that this idea is strange, puzzling, beyond belief, false, meaningless or at any rate defective. The first section develops the alleged problem. The burden of this paper, however, is not to discuss the merits of this idea but rather to measure the damage in case the idea turns out to be defective indeed. This is done by substantiating the claim that this idea indeed underlies large and important stretches of our social and institutional life. Section 2 substantiates that claim by presenting the results of a web search on the use of what I call “deontological epistemic expressions”, i.e. expressions in which deontological and epistemological notions (both broadly construed) are combined; examples are “obligation to believe”, “not permitted to forget”, “right to know”. The ubiquitous use of these expressions, I argue, is linguistic evidence for the claim that the contested idea indeed pervades our social life. Linguistic evidence, however, can be frail and misleading. From the fact that we say that the shade is moving we cannot conclude that shades really exist; likewise it may not be permitted to conclude from the ubiquitous use of deontological epistemic expressions that there really are doxastic obligations (and hence doxastic responsibilities). The third section, therefore, moves beyond the linguistic evidence and discusses two social institutions, viz. education and law as we find them in modern Western societies, and argues that they cannot be made sense of unless the contested idea is in place. Educational and legal systems of course vary greatly throughout the Western world. Such differences as exist, however, are irrelevant for the claim I will be making in this paper. The final section states the conclusion.