Algumas considerações sobre lógica<br>Some considerations on logic

Abstract

This objective point out some birth steps of logic in ancient Greece highlighting the contribution of the first philosophers including Heraclitus and Parmenides. Highlighting becoming, stated at first that everything changes, that change is real, and the view taken by Parmenides that the real and true is what never changes: the being is non-being is not. It also highlights the contribution of Plato with the epistemic principle that makes and gives presence to the real. First criterion for logic for rationality. And Aristotle with logos whose purpose was to show the correct way to build the knowledge and scientific evidence. Also studied the contribution in the medieval period especially with the flowering of scholasticism of some of the most important and brilliant philosophers who contributed to the development of Aristotelian logic, including Abelard, Aquinas and William of Ockham. He worked with the division of logic in most logic also called material logic that determines the particular and special rules laws and less than or formal logic laying down the conditions of conformity of thought working with the seizure of definitions and the term, understanding and extension, judgment and proposition, reasoning and argument. Also notable was the deductive reasoning or syllogism, the legal syllogism and inductive reasoning.