In the attempt to understand who it is the human being, leaving of itself exactly, Ren, in its Metaphysical meditations, sets to doubt it the existence of everything and conceives a God as malignant Genius whose scienter is not another seno to deceive the citizen. This deceptive God is part of the hyperbolic doubt of Discardings, which after to place all suspended existence in and annular all knowing reaches its apex in an only point of certainty: the thought. A thing is at least certain for it: of that it is thinking. In this to doubt everything, Discardings (apud, QUINET, 2001, p.15) places: ' ' … meeting here that the thought is one attribute that belongs to me; it cannot only be detached of me.
I am, I exist that is certain, but for how much time? The time that I to think, therefore, perhaps, its I left to think I I could leave to exist. I now do not admit nothing that is not necessarily true: I am not seno a thing that pensa' '. The citizen that is: a thing whose substance is thought. The citizen of the thought considers true everything what the reason conceives of clear and distinct form, as, for example, the idea of God that Discardings it not more restitutes from the third meditation as a malignant genius, but as author of the existence. When claiming the Other (external) as a pledge of thinking and of existing, either this the holy ghost or human being, the other, in short, guarantees the citizen. 2.3SIGMUND FREUD AND the CARTESIAN INHERITANCE Ren Discardings left between physicists and philosophers an inestimable legacy.
Sigmund Freud takes ownership of this inheritance in the formularization of its methodology of research: The Psychoanalysis. Freud makes its first publication in 1895, falecendo in 1939. With its participation the world of psychology modifies forever.