Jianing Wu

Philosopher Coasters 3 - Descartes

JIANING WU -

Descartes (1596 – 1650)


Perhaps now it is appropriate to define metaphysics, for Descartes’ famous quote --

cogito ergo sum

-- is the answer to a metaphysical quest via an epistemological approach.

In the 20th century, philosophers likened metaphysics to mean “above physics.” While some don’t like this interpretation, it captures the concept of metaphysics as a study of laws beyond physical laws. Metaphysics is a study of first principles that dictate the world and our worldly experiences. Similar to physics, the question metaphysics tries to answer is – how does the world work? – albeit not from the perspective of physical forces and movements.

Descartes disliked the then scholastic approach in understanding the world through sensations and experiences. He asked, how do we know if our cognition of the world really is what is out there? If our understanding of the world is built upon experiences and our experiences were “false,” then everything including science would collapse. In other words, without a proven foundation of knowledge, human beliefs are susceptible to falsehood and systematic beliefs are impossible.

Descartes’ final solution to this question was a happy one. He demonstrated via a proof of God’s existence that innate knowledge, a priori to our experiences, is possible (I will not elaborate on the proof here, since it is a lengthy one). This innate knowledge that we humans inherently have establishes a universal ground of understanding that we share, and its validity is guaranteed by the good-willed God. At the very core of this proof is the proof of him as a “thinking thing” (1-18, Meditations on First Philosophy), captured by “I think, therefore I am” (Part IV, Discourse on the Method).

“I think, therefore I am” is another quote that deserves to be read three times. The first level of interpretation, which Descartes took it to be, is that:

  1. the action of thinking presupposes a subject;
  2. the fact that he is thinking about this very fact proves the activity of thinking as valid;
  3. therefore the subject, which is the “I” exists;
  4. consequently, he is a “thinking thing” that exists
  5. if a “thinking thing” exists, then immediate innate knowledge could exist, since “I think, therefore I am” is an example of this awareness

Later analyses on the statement question step 3, on what this “I” entails. Does it imply an individual or merely a consciousness? Another stronger point of attack is whether a self-predicating sentence can serve to prove its validity. We will not go into the technical details here.

Although Descartes’ theory of knowledge might suffer attacks, it marks the start of modern philosophy as rationality and logical deduction reign supreme. Descartes’ introduction of “radical doubt” reshaped how philosophy should be approached. Through his establishment of the correspondence between our cognition and the world, his epistemology reached in accordance with metaphysics to explain how the world and our worldly experience are possible.