Descartes' Major Tenets Descartes Major Tenets

Descartes was one of the most well-respected thinkers of his time, and he applied his special brand of logic to a wide-variety of disciplines, most notably mathematics and philosophy. The Cartesian approach to philosophy, like many approaches to philosophy, looked at the interaction of the mind and the brain. Were the mind and the brain one united organism, did they interact with one another, was one of them superior or more powerful than the other? All of those questions were critical to Descartes' explanation of the universe.

As explained by Nonaka and Takeuchi, the body has an extension into space but cannot think. In contrast, the mind has no extension into space, but can think. Nonaka and Takeuchi used one of Descartes' most famous examples, his explanation of the qualities of honey wax, to explain his dualistic approach to the world. "As for his epistemology, Descartes argued that honey wax's qualities, such as taste, scent, color, and size, which are apparent to the senses, change if we put it near fire; therefore, wax itself cannot be sensible. Thus true knowledge about external things can be obtained by the mind, not the senses" (Nonaka & Takeuchi, 2008).

The featured example of Cartesian philosophy in the textbook only provides a brief glimpse into Descartes' philosophy. It is important to understand that there were significant shifts in Descartes' philosophy throughout his lifetime, and that experts vary somewhat significantly in how they choose to divide Cartesian philosophy (Hatfield, 2008). Descartes' new metaphysics focused on five different elements: (1) how do our minds know; (2) the mark of truth; (3) the nature of reality; (4) the mind-body relation; and (5) God and error.

The first tenet in Cartesian metaphysics is the understanding of how the mind knows. A cornerstone of Cartesian philosophy was that human beings had some innate knowledge and were capable of discovering additional facts. These facts would allow them to understand the fundamental truths about reality....

However, he believed that Aristotelian philosophy was flawed because of its dependence on the senses. He believed that the senses were unreliable and, therefore, could not be source of knowledge about the nature of substances. Instead, Descartes' view was that "human intellect is able to perceive the nature of reality through a purely intellectual perception" (Hatfield, 2008). To Descartes, clear and distinct intellectual perception, independent of the senses, is the mark of truth (Hatfield, 2008). However, Descartes does not suggest that the senses have no role in knowledge acquisition. First, "he acknowledged that the senses are usually adequate for detecting benefits and harms for the body" (Hatfield, 2008). Second, "he recognized that the senses have an essential role to play in natural philosophy" (Hatfield, 2008).
Next, Descartes discusses the mark of truth, which is clarity and distinctness of intellectual perception. However, an objection to that statement is, "If clarity and distinctness is the mark of truth, what is the method for recognizing clarity and distinctness?" (Hatfield, 2008). Descartes acknowledges that individuals can be wrong in their beliefs, but also asserts that "we have a clear and distinct perception of something, if when we consider it, we cannot doubt it (7:145) That is, in the face of genuine clear and distinct perception, our affirmation of it is so firm that it cannot be shaken" (Hatfield, 2008). According to Descartes, any act of judgment requires intellect and will. The intellect perceives the content of the judgment, while the will affirms or denies that content (Hatfield, 2008).

The third cornerstone of Cartesian philosophy is the nature of reality. "The main metaphysical results that describe the nature of reality assert the existence of three substances, each characterized by an essence. The first and primary substance is God, whose essence is perfection. In fact, God is the only true substance, that is, the only being that is capable of existing on its own" (Hatfield, 2008). The other two substances, mind and matter, are…