The form of this paper, which has more than one purpose, needs a word of explanation and perhaps of excuse. I had had it in mind to bring together and discuss a number of passages of Plautus in which gratus or gratia occurred. Then I came across an interesting paper by Professor L. R. Palmer in Hommages à Max Miedermann , Bruxelles, 1956, pp. 258–69, entitled ‘The Concept of Social Obligation in Indo-European: A Study in Structural Semantics’. There Palmer dealt, (...) among other things, with gratus and related words; he seemed to me, however, to treat the Latin evidence, the greater part of it from Plautus, in a way which I felt to be mistaken. In addition it seemed that a preconceived theory, derived from a special interpretation of the Mycenean tablets, was being read into Roman thought and institutions against the evidence. I have therefore taken the opportunity to discuss the passages of Plautus in which I was first interested within a general examination of Palmer's treatment of the Latin evidence for his theory. (shrink)