Ancient Greek Logic: Aristotle Beginning Modern Logic: Leibniz Scientific articles on formal aspects of Ancient Western and Indian Logic © Klaus Glashoff Medieaval Indian Logic: Dignaga Quotation of the day: "There is, then, a sense in which ontology arises in a formal system even before the system obtains an interpretation of its variables. The ontology becomes, so to speak, built into the system as soon as we decide to differentiate one type of variable from another... ." Jack Kaminski,Language and Ontology