Abstract

Aristotle’s presentation of ontology advanced at the beginning of the fourth book of Metaphysics is universally known: “there is a science which studies being qua being...”. Needless to say, this is a familiar sentence: unfortunately, it is also quite an odd one. Why Aristotle does not simply say that ontology is the theory of being? Is there any difference between ‘theory of being’ and ‘theory of being qua being’? In brief, the problem is to decide whether the two expressions ‘the study of being’ and ‘the study of being qua being’ are equivalent. If they are, the ‘qua’ does not play any interesting role. On the contrary, if the two expressions are different, that is to say, if there is a difference between the study of being (simpliciter) and the study of being qua being, we should study the role played by the (operator) ‘qua’