"Cogito ergo sum"

"I think, therefore I am"

     The famous quote by Rene Descartes is depicted perfectly by François-Auguste-René Rodin's interesting sculpture, The Thinker. Descartes' thought provoking quote is explained in a very interesting and almost depressing manor. If one knows nothing else, thinking is to exist. Even to doubt is to think, therefore to doubt is to think and to think is to exist. This is a rationalist view of human nature. We do not know why we are here, and there is no real purpose, but as long as you can doubt and ultimately think, you exist.

Reason, the Basis of all Knowledge

A rationalist uses logic as the chief principle in knowledge. This means that everything we learn and we use reason in every situation above all else.
This diagram explains the connection between reason and all else. It is the source of knowledge in that we use logic to obtain knowledge. Our reason also ultimately provides justification for our morals and beliefs. Reason dictates how we see and view certain situations and our opinion of right and wrong toward that situation.

Description of Rationalism

Rationalism: The philosophical view that regards reason as the chief source and test of knowledge. Holding that reality itself has an inherently logical structure, the rationalist asserts that a class of truths exists that the intellect can grasp directly. There are, according to the rationalists, certain rational principles—especially in logic and mathematics, and even in ethics and metaphysics—that are so fundamental that to deny them is to fall into contradiction. The rationalist’s confidence in reason and proof tends, therefore, to detract from his respect for other ways of knowing. - Encyclopædia Britannica

Time-line of Major Events in the Rationalist View

·         Plato’s Allegory of the chariot: there is a chariot being pulled by two horses. One horse represents a person’s appetite, the basic drives such as the drive for food, lust and power. The other horse represents spirit or emotion, this horse is ruled by emotion and tends to do good. The chariot is representative of reason. The chariot, representing reason must control both the spirit/emotion and the appetite. This allegory is the human mind and we must control ourselves with reason. Plato’s allegory of the chariot is the first rationalist view of human nature.

·         Most aspects of the Rationalist view are reactions against traditional Greek beliefs mainly from Aristotle. He believed that the earth was the center of the universe, the sun and planets orbit the earth and that the stars are fixed, unchanging orbs. The scientific and rationalist views challenged this beginning in the 17th century. 

17th Century
·         In the years between 1601-1700, the rationalist view was born. Beginning with Descartes, it was the belief that everything in the world can be explained with logic and reason. Descartes was a mathematical genious and tried to apply formulas for life. He also introduced the idea of our senses being figments of our mind and that they can deceive us
      Senses deceiving us: Descartes in one of his original works, Principles of Philosophy [translated to English], believes that all the senses deceive us. He used the example of our sight. Stating that we see the setting sun as a roughly two-inch wide object in the sky, but in fact, our reason tells us that the sun is actually almost infinitely times larger than we see it in the sky.

View of sun from earth vs. sun to scale with various planets
·         Descartes states that there must be a god or higher being. This is because we all have a general idea of perfection and we compare everything to it. Descartes says this is a God or higher being that we base this idea of perfect.

  •        Descartes also believed in a pinnacle point of rationalism called dualism. Dualism is the theory that the mind and body are separate entities. This idea was created as far back as Plato and Aristotle. Descartes took this concept further saying that the mind is a non-physical substance. This means that what the senses tell us is happening, may not actually be true. This type of dualism is called substance dualism. It can be separated into two types of substance, which are mental and material. According to Descartes, the mental is not a physical substance, this is the mind, and it cannot move. The material is a physical substance which cannot think. Therefore, the combination of the material, which is the body, and the mental, which is the mind, comes together.

Modern Day
           Rationalism states that the mental, or mind, of a human is ultimately free. The material, or body, of a person is not free. The body is separate from the mind in that it can operate on its own, but not know the true meaning or direction of its movements. The mind is the soul which makes us who we are. Because the mind is the deciding power in a human and it is free, then we are considered free beings. Not controlled by a god or higher being, we can decide our own course of action. Some rationalists do still believe there is a god or higher being because all humans are born with an idea of what perfection is. Most Rationalists agree that we get the idea of perfection from some place and most say that it is from a God or higher being which is perfect. Because the mind and soul is the main entity in a human, and controls the material (body) but still has decision in our day to day activities, we are free beings.

From René Descartes's Original work, Renatus Cartesius [Principles of Philosophy]

          Rationalists can be categorized into following one of three modern theses.*
-          The intuition/deduction thesis – some knowledge is obtained by intuition alone, others are deduced from sources that are intuited.
-          The innate knowledge thesis – this thesis states that we obtain some knowledge in specific areas without any experience. The thesis states that it is not intuited or deduced, but is part of our rational nature
-          The innate concept thesis – this states that some knowledge is already obtained through human nature. Unlike the innate knowledge thesis, it is triggered from the unconscious to the conscious by a sense experience. Though the experience that triggers this, the knowledge is not from the experience, it is from our nature.

 * As explained by the Stanford Encyclopedia of Philosophy (full citation in bibliography)