In this paper, I shall try to enhance our understanding of Aristotle's thought by relating it to certain contemporary problems and insights of philosophical logicians. One of the most central current issues in philosophical logic is a challenge to a hundred-year old dogma. Almost all twentieth-century philosophers in English-speaking countries have followed Frege and Russell and claimed that the words for being in natural languages — "is," "ist," ἔστι etc.— are ambiguous between the is of predication, the is of existence, the is of identity, and the generic is. The significance of this ambiguity thesis has not been limited to topical discussions but has extended to historical studies, including studies of ancient Greek philosophy. A generation or two of scholars working in this area used the Frege-Russell ambiguity thesis as an important ingredient of their interpretational framework.
Many of us have by this time come to suspect that the Frege-Russell ambiguity claim is completely anachronistic when applied to Aristotle. The sources of this dark professional secret are various, ranging from G. E. L. Owen's brilliant studies of Aristotle on being to Charles Kahn's patient examination of the Greek verb τὸ εῖναι . Most of us good Aristotelians have nevertheless remained in the closet. As was illustrated by the fate that befell the first major study in which Plato's failure to draw the Frege-Russell distinction was noted, most of the unliberated Aristotelians seem to have thought that to note Aristotle's failure to draw the distinction is to accuse him of an abject logical mistake. Accordingly, we have shied away from such impiety. It is time for some consciousness-raising, however. It is not convincing enough merely to register the inapplicability of the modern distinction to Aristotle. We need a deeper understanding of the whole situation. In an earlier paper, I have shown that there need not be anything logically or semantically wrong with a theory which treats the verbs of being as not exhibiting the Frege- Russell ambiguity. (See Hintikka 1979.) More than that: not only can we now say that Aristotle’s procedure is free from any taint of fallacy; he may have been a better semanticist of natural language than Frege and Russell in this particular respect.
Hintikka, Jaakko, "The Unambiguity of Aristotelian Being" (1981). The Society for Ancient Greek Philosophy Newsletter. 238.