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: "In very abstract studies such as philosophical logic, ... the subject-matter that you are supposed to be thinking of is so exceedingly difficult and elusive that any person who has ever tried to think about it knows you do not think about it except perhaps once in six months for half a minute. The rest of the time you think about the symbols... ".Bertrand Russell?