René Descartes :- The Embodiment of Modern Philosophy, Rationalism, Logic and Mathematics.

If we take a quick glance into the history of Western Philosophy, we come across the ancient greek philosophers talking about natural sciences, cosmology, pure mathematics, subjectivism vs realism etc. in the pre-socratic period.

Then comes the classic period which centres around socrates and the next two generations of his students, including Plato, Aristotle and others. We find here discussions mainly related to truth, life, virtue, knowledge and topics of philosophical concern, including physics, biology, zoology, metaphysics, aesthetics, poetry, theater, music, rhetoric, politics, and logic. Greek philosophy deserves a complete separate blog in itself.

The central theme of today's blog, however, is classical modern philosophy. The period of early modern philosophy is considered to be around 17th and 18th centuries when scholars were discussing a wide range of ideas centered on the value of human happiness, the pursuit of knowledge obtained by means of reason and the evidence of the senses, and ideals such as liberty, progress, toleration, fraternity, and constitutional government.

Early Modern Western Philosophy branches into two categories called rationalism and empiricism. Both are extreme opposites.

In philosophy, rationalism is the epistemological view that "regards reason as the chief source and test of knowledge".

The rationalists believed that reality has an intrinsically logical structure. Because of this, the rationalists argued that certain truths exist and that the intellect can directly grasp these truths. That is to say, rationalists asserted that certain rational principles exist in logic, mathematics, ethics, and metaphysics that are so fundamentally true that denying them causes one to fall into contradiction.

The empiricists think that all knowledge comes from sensation which is triggered by objects existing in the external world, with thoughts being a kind of computation. Philosophical empiricists hold no knowledge to be properly inferred or deduced unless it is derived from one's sense-based experience. This view is commonly contrasted with rationalism, which states that knowledge may be derived from reason independently of the senses.

Experts and scholars believe that modern philosophy culminated into scientific revolution and the era of inquiry, logic and skepticism with the advent of René Descartes, a French philosopher, scientist, mathematician and a staunch rationalist.

Descartes is widely considered a seminal figure in the emergence of modern philosophy and science. Mathematics, logic and rational inquiry were his primary weapons to seek answers, as we find a whole separate systematic method to doubt something and seek answers, in his philosophy. It is called Cartesian doubt.

Cartesian doubt is methodological. It uses doubt as a route to certain knowledge by identifying what can't be doubted. The fallibility of sense data in particular is a subject of Cartesian doubt.

I find that Vedanta philosophy's Neti, Neti approach meaning "Not this" "Not this" closely resembles Cartesian doubt. In the Nirvana Shatakam of Adi Shankaracharya, we observe him logically negating all that a human isn't, like one's body, mind, thoughts etc. to truly perceive what is his real, true nature. 

Cartesian doubt is a systematic process of being skeptical about (or doubting) the truth of one's beliefs, which has become a characteristic method in philosophy.

"Several years have now elapsed since I first became aware that I had accepted, even from my youth, many false opinions for true, and that consequently what I afterward based on such principles was highly doubtful; and from that time I was convinced of the necessity of undertaking once in my life to rid myself of all the opinions I had adopted, and of commencing anew the work of building from the foundation..."

            —Descartes, Meditation

I find Descartes' idea similar to the idea of Jiddu Krishnamurthy, who too, advocated that the conditioning and prejudices of the human mind makes it dull and incapable of grasping the true nature of existence. Infact, this idea is reflected more or less in all inquiry-based philosophies. 

"The first was never to accept anything for true which I did not know to be such; that is to say, carefully to avoid precipitancy and prejudice, and to comprise nothing more in my judgment than what was presented to my mind so clearly and distinctly as to exclude all ground of doubt."

Additionally, Descartes' method has been seen by many as the root of the modern scientific method. This method of doubt was largely popularized in Western philosophy by René Descartes, who sought to doubt the truth of all beliefs in order to determine which he could be certain were true.

In one of his writings, Descartes recalls:-

"I entirely abandoned the study of letters. Resolving to seek no knowledge other than that of which could be found in myself or else in the great book of the world, I spent the rest of my youth traveling, visiting courts and armies, mixing with people of diverse temperaments and ranks, gathering various experiences, testing myself in the situations which fortune offered me, and at all times reflecting upon whatever came my way to derive some profit from it."

This hints what special place rational inquiry and doubting had in Descartes' philosophy. 

René Descartes, the originator of Cartesian doubt, put all beliefs, ideas, thoughts, and matter in doubt. He showed that his grounds, or reasoning, for any knowledge could just as well be false. Sensory experience, the primary mode of knowledge, is often erroneous and therefore must be doubted. For instance, what one is seeing may very well be a hallucination. There is nothing that proves it cannot be. In short, if there is any way a belief can be disproved, then its grounds are insufficient.

While methodic doubt has a nature, one need not hold that knowledge is impossible to apply the method of doubt. Indeed, Descartes' attempt to apply the method of doubt to the existence of himself spawned the proof of his famous saying, "Cogito, ergo sum" (I think, therefore I am). That is, Descartes tried to doubt his own existence, but found that even his doubting showed that he existed, since he could not doubt if he did not exist. 

"I doubt, therefore I think. I think, therefore I am." is the first principle of Cartesian philosophy.

Descartes continued all his life to publish works on philosophy, mathematics, science and logic. You might be baffled to know how much he has thought for us, that is, has had his intellectual contributions to a wide range of subjects.

His notable ideas, apart from philosophy, were immense contributions to analytical geometry, algebra, cartesian coordinate system, imaginary numbers, folium of descartes, conservation of momentum, rule of signs', etc.

I think René Descartes could think exceptionally well. That too, not because he was a gifted mind, but due to his extreme skepticism and training of mind to think rationally. Really, he inspires us how to think!

Thanks,

Daksh Parekh.