RENÉ DESCARTES’ QUEST FOR INDUBITABILITY

DOMENIC MARBANIANG

Teaching Document. 2019

BACKGROUND: LIFE AND WORKS 1. He was born in La Haye en Touraine (now Descartes, Indre-et-Loire), France, on 31 March 1596 2. He was a contemporary to Francis Bacon, Galileo Galilei, Blaise Pascal, Isaac Newton, Baruch Spinoza, Thomas Hobbes, Gottfried Wilhelm Leibniz, and William Shakespeare. 3. He was trained in mathematics, physics, philosophy and law; and in his quest for truth, he spent much of his youth “traveling, visiting courts and armies, mixing with people of diverse temperaments and ranks, gathering various experiences” 4. He also worked in the Dutch army for a while. 5. On returning home (to La Haye), in 1623, he sold all his property to invest in bonds, which provided him a sizable income for the rest of his life. 6. From 1628, he lived and worked in Netherlands. 7. He most influential publications are Geometry, Bioptrics, and Discourse on Method (1637), Meditations on First Philosophy (1641), Principles of Philosophy (1644) 8. Descartes’ writings were condemned at the University of Utrecht (Netherlands) in 1643, which forced him to flee to the Hague. 9. In 1649, he moved to Sweden on invitation of Queen Christina. 10. The next year, in 1650, he contracted pneumonia and died.

THE THRESHOLD ERA OF MODERNISM 1. Francis Bacon is considered to be the “father of modern jurisprudence” and the “father of the scientific method”. 2. Galileo is considered the "father of observational astronomy", the "father of the scientific method", and the "father of modern science". 3. Isaac Newton is considered to be the “father of classical physics” and the “father of modern science” 4. René Descartes is considered to be the “father of analytical geometry”, the “father of modern Western philosophy” and the “father of continental rationalism”.

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ACCORDING TO THE COLUMBIA ELECTRONIC ENCYCLOPEDIA, 6TH ED. COPYRIGHT © 2012, COLUMBIA UNIVERSITY PRESS,

Mathematics was his greatest interest; building upon the work of others, he originated the Cartesian coordinates and Cartesian curves; he is often said to be the founder of analytical geometry. To algebra he contributed the treatment of negative roots and the convention of exponent notation. He made numerous advances in optics, such as his study of the reflection and refraction of light. He wrote a text on physiology, and he also worked in psychology; he contended that emotion was finally physiological at base and argued that the control of the physical expression of emotion would control the emotions themselves. His chief work on psychology is in his Traité des passions de l'âme (1649).

Cartesian coordinate system with a circle of radius 2 centered at the origin marked in red. The equation of a circle is (x − a)2 + (y − b)2 = r2 where a and b are the coordinates of the center (a, b) and r is the radius. (xyz used to denote variables, and abc used to denote (Wikipedia)

DESCARTES’ INFLUENCE: 1. Descartes’ logical method from certitude to certitude was a break away from the scholastic Aristotelian one of empirical probabilism and influenced much of later science and philosophy. 2. His ideas revolutionized the role of mathematics in science and philosophy. 3. He formulated the cartesian coordinates, is considered the father of analytical geometry (combining geometry with algebra), and his work laid the basis for the development of calculus. 4. His formulation of scientific laws of nature, viz. that “that each thing always remains in the same state; and consequently, when it is once moved, it always continues to move” and that “all movement is, of itself, along straight lines” were later incorporated into Newton’s first law of motion. 5. Descartes’ view that all truth is interlinked through a fundamental truth such as the cogito provided a basis for the hypothesis of the uniformity of nature and its laws of operation and the progress of science. 6. Descartes’ reliance on intuition and deduction in opposition to authority and sense-experience was a break away from reliance on religious authority, tradition, and testimony. 7. Descartes’ rationalism highly accentuated the Protestant Reformation influence

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towards the secularization of society and the individual’s autonomous intellectual freedom. 8. Descartes’ mind-body dualism became an integral theme of much future philosophical discussion. 9. Descartes’ “evil demon” or “evil god” hypothesis is a continuing problem in philosophy of mind and reality. 10. Descartes’ view that animals do not have souls and so do not suffer pain had a considerable impact on Western animal ethics.

SOME ASSOCIATED “ISMS” ● Internalism ● Foundationalism ● Rationalism ● Intuitionism ● Methodological Skepticism ● Theological voluntarism ● Mind-body dualism

DESCARTES’ QUEST FOR TRUTH AND MEANING

I had always a most earnest desire to know how to distinguish the true from the false, in order that I might be able clearly to discriminate the right path in life, and proceed in it with confidence. (Discourse on the Method)

DESCARTES’ DOUBTS

From my childhood, I have been familiar with letters; and as I was given to believe that by their help a clear and certain knowledge of all that is useful in life might be acquired, I was ardently desirous of instruction. But as soon as I had finished the entire course of study, at the close of which it is customary to be admitted into the order of the learned, I completely changed my opinion. For I found myself involved in so many doubts and errors, that I was convinced I had advanced no farther in all my attempts at learning, than the discovery at every turn of my own ignorance.

HIS VIEW OF MATHEMATICS

I was especially delighted with the mathematics, on account of the certitude and evidence of their reasonings; but I had not as yet a precise knowledge of their true use; and thinking that they but contributed to the advancement of the mechanical arts, I was astonished that foundations, so strong and solid, should have had no loftier superstructure reared on them.

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HIS AVOIDANCE OF THEOLOGY

I revered our theology, and aspired as much as any one to reach heaven: but being given assuredly to understand that the way is not less open to the most ignorant than to the most learned, and that the revealed truths which lead to heaven are above our comprehension, I did not presume to subject them to the impotency of my reason; and I thought that in order competently to undertake their examination, there was need of some special help from heaven, and of being more than man.

HIS DISILLUSIONMENT WITH PHILOSOPHY

Of philosophy I will say nothing, except that when I saw that it had been cultivated for many ages by the most distinguished men, and that yet there is not a single matter within its sphere which is not still in dispute, and nothing, therefore, which is above doubt, I did not presume to anticipate that my success would be greater in it than that of others; and further, when I considered the number of conflicting opinions touching a single matter that may be upheld by learned men, while there can be but one true, I reckoned as well-nigh false all that was only probable.

HIS REJECTION OF THE OTHER “SCIENCES”

As to the other sciences, inasmuch as these borrow their principles from philosophy, I judged that no solid superstructures could be reared on foundations so infirm; and neither the honor nor the gain held out by them was sufficient to determine me to their cultivation: for I was not, thank Heaven, in a condition which compelled me to make merchandise of science for the bettering of my fortune; and though I might not profess to scorn glory as a cynic, I yet made very slight account of that honor which I hoped to acquire only through fictitious titles.

DESCARTES’ PRELIMINARY ACTION STEP

For these reasons, as soon as my age permitted me to pass from under the control of my instructors, I entirely abandoned the study of letters, and resolved no longer to seek any other science than the knowledge of myself, or of the great book of the world. I spent the remainder of my youth in traveling, in visiting courts and armies, in holding intercourse with men of different dispositions and ranks, in collecting varied experience, in proving myself in the different situations into which fortune threw me, and, above all, in making such reflection on the matter of my experience as to secure my improvement.

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3 MAIN OBSERVATIONS: 1. WHAT IS NEEDED IS PRACTICAL TRUTH.

For it occurred to me that I should find much more truth in the reasonings of each individual with reference to the affairs in which he is personally interested, and the issue of which must presently punish him if he has judged amiss, than in those conducted by a man of letters in his study, regarding speculative matters that are of no practical moment, and followed by no consequences to himself….

2. OPINIONS THAT ARE RELATIVE TO CUSTOMS AND CULTURES FLUCTUATE AND, THEREFORE, ARE NOT ABSOLUTE.

I took into account also the very different character which a person brought up from infancy in France or Germany exhibits, from that which, with the same mind originally, this individual would have possessed had he lived always among the Chinese or with savages, and the circumstance that in dress itself the fashion which pleased us ten years ago, and which may again, perhaps, be received into favor before ten years have gone, appears to us at this moment extravagant and ridiculous. I was thus led to infer that the ground of our opinions is far more custom and example than any certain knowledge.

3. POPULARITY IS NO GUARANTEE TO TRUTH

And, finally, although such be the ground of our opinions, I remarked that a plurality of suffrages is no guarantee of truth where it is at all of difficult discovery, as in such cases it is much more likely that it will be found by one than by many. I could, however, select from the crowd no one whose opinions seemed worthy of preference, and thus I found myself constrained, as it were, to use my own reason in the conduct of my life.

DESCARTES’ 4 PRECEPTS:

1. Accept only what is indubitably certain.

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

2. Break each problem into bits to solve.

To divide each of the difficulties under examination into as many parts as possible, and as might be necessary for its adequate solution.

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3. Move from the Easiest to the More Complex, from Certainty to Certainty.

To conduct my thoughts in such order that, by commencing with objects the simplest and easiest to know, I might ascend by little and little, and, as it were, step by step, to the knowledge of the more complex; assigning in thought a certain order even to those objects which in their own nature do not stand in a relation of antecedence and sequence.

4. Rigorously Review and Re-test Everything

In every case to make enumerations so complete, and reviews so general, that I might be assured that nothing was omitted.

THE INSPIRATION BEHIND THE METHOD: MATHEMATICS

The long chains of simple and easy reasonings by means of which geometers are accustomed to reach the conclusions of their most difficult demonstrations, had led me to imagine that all things, to the knowledge of which man is competent, are mutually connected in the same way, and that there is nothing so far removed from us as to be beyond our reach, or so hidden that we cannot discover it

DESCARTES’ 4 MAXIMS OF SAFETY 1. “Obey the laws and customs of my country” and be faithful to my faith, avoiding extremes. 2. “Be as firm and resolute in my actions as I was able,” even if I feel lost… like a man lost in the forest will keep walking straight so that he may reach some place, preferable to the middle of the forest. 3. “To endeavor always to conquer myself rather than fortune, and change my desires rather than the order of the world” 4. “Devoting my whole life to the culture of my reason, and in making the greatest progress I was able in the knowledge of truth, on the principles of the method which I had prescribed to myself.”

DESCARTES’ RESOLUTIONS 1. Start by doubting everything that is not indubitable. 2. Regard all dubitable things as false. 3. Use the method of doubt only when searching for truth. Otherwise, just go on with life as usual. (Methodological skepticism is practically unlivable).

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DESCARTES’ PRELIMINARY DISCOVERIES

1. ALL THINGS PERCEIVED BY THE SENSES (SENSIBLE THINGS) ARE DUBITABLE. Argument (a) 1. If the senses sometimes deceive us, then they are unreliable. 2. They sometimes deceive us. 3. Therefore, they are unreliable.

Argument (b) 1. If objects in both dream and waking state seem equally real and non differentiable, then they both are dubitable. 2. Objects in both dream and waking state seem equally real and non differentiable. 3. Therefore, they both are dubitable.

2. MATHEMATICAL DEMONSTRATIONS ARE DUBITABLE. Argument (a) 1. If we are occasionally deceived in matters of knowledge,(A) then it is not more impossible that an all-powerful God may have created us in a way that we are always deceived. (B) 2. A 3. Therefore, B.

Argument (b) 1. If we suppose that God is not almighty and perfect (A), then it entails that we are imperfect and deceivable. (B) 2. If we supposed that God is almighty, then argument (a) 3. If A of argument (b) 4. Then, B of the same.

3. THE FIRST THING THAT IS INDUBITABLE IS “I EXIST” 1. I think 2. Therefore, I exist.

Cogito ergo sum (Latin) je pense, donc je suis (French)

Not the same as: 1. Whatever thinks must also exist 2. I think 3. Therefore, I exist

Cogito ergo sum is intuited, not inferred.

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While we thus reject all of which we can entertain the smallest doubt, and even imagine that it is false, we easily indeed suppose that there is neither God, nor sky, nor bodies, and that we ourselves even have neither hands nor feet, nor, finally, a body; but we cannot in the same way suppose that we are not while we doubt of the truth of these things; for there is a repugnance in conceiving that what thinks does not exist at the very time when it thinks. Accordingly, the knowledge, I THINK, THEREFORE I AM, is the first and most certain that occurs to one who philosophizes orderly.

4. COGITO ERGO SUM ENTAILS MIND-BODY DUALISM

1. If the mind is indubitable but the body is dubitable (A), then they are not the same (B). 2. A 3. Therefore, B.

5. THE MIND IS ABLE TO DOUBT THE EXISTENCE OF OTHER THINGS, BUT IT IS IMPOSSIBLE TO LOGICALLY DENY THE EXISTENCE OF GOD

Argument (a) 1. The idea of an all-perfect being is comprised of necessary and eternal existence 2. If the mind has the idea of an all-perfect being, then that being necessarily and eternally exists.(If A then B) 3. The mind has such an idea (A) 4. Therefore, an all-perfect being exists. (B)

Argument (b) 1. We have a concept of things, e.g. a machine on the basis of either previously seeing another machine or because (if we have never seen the like) we have invented it ourselves. 2. We have the concept of an all-perfect being. 3. We have neither seen such a being nor have ever created such a being (for nothing around us nor we are all-perfect). 4. Therefore, the concept of an all-perfect being must have some other source. 5. That source must be all-perfect, or else it cannot produce the concept of an all- perfect being. 6. Therefore, such a source, viz. an all-perfect being necessarily exists.

Argument (c) 1. If I have the concept of something more perfect than myself, then I am not the source of my own being. 2. I have the concept of something more perfect than myself 3. Therefore, I am not the source of my own being.

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1. If I am not the source of my own being because I am not all-perfect, then an all- perfect being must be the source of my being. 2. I am not the source of my own being because I am not all-perfect. 3. Therefore, an all perfect being is the source of my being.

Argument (d) 1. If contingent things continually exist (endure, are conserved), then a self- existent reason for their endurance necessarily exists. 2. Contingent things continually exist. 3. Therefore, a self-existent reason for their endurance (God) necessarily exists.

6. THE IDEA OF GOD ALSO INCLUDES THE ATTRIBUTES OF GOD for, reflecting on the idea we have of him which is born with us, we perceive that he is eternal, omniscient, omnipotent, the source of all goodness and truth, creator of all things, and that, in fine, he has in himself all that in which we can clearly discover any infinite perfection or good that is not limited by any imperfection

7. GOD IS NOT A MATERIAL BEING AND DOES NOT PERCEIVE THINGS VIA PHYSICAL SENSE ORGANS

1. All material (corporeal) bodies are divisible and so are imperfect. (All A are B) 2. God is all-perfect (C is not B) 3. Therefore, God is not a material (corporeal) being. (C is not A)

8. GOD CANNOT DECEIVE US (ANSWER TO THE MATRIX PROBLEM) 1. If God is all-perfect, then he will not deceive us (for imperfection and falsehood cannot proceed from the all-perfect and veracious) 2. God is all-perfect 3. Therefore, he does not deceive us (i.e., we are not in a matrix situation)

9. ALL THAT WE CLEARLY PERCEIVE IS TRUE; THUS, WE ARE DELIVERED FROM THE DOUBTS POSED EARLIER

1. If God does not deceive us, then our faculty of knowledge is not perverted (is reliable) 2. God does not deceive us 3. Therefore, our faculty of knowledge is not perverted (is reliable)

1. If our faculty of knowledge is reliable, then all that we clearly perceive is true. 2. Our faculty of knowledge is reliable 3. Therefore, all that we clearly perceive is true.

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IS THIS BEGGING THE QUESTION? Descartes would say, “No”

Because both “I exist” and “God exists” are intuited (a priori), not inferred.

Doubts regarding God’s existence arise from biases and from not steadily fixing “our thoughts on the contemplation of the all-perfect Being”

10. MATHEMATICAL TRUTHS ARE THE CLEAREST AND THEREFORE INDUBITABLE

1. If something is clearly perceived, then it is indubitable. 2. Mathematical truths are clearly perceived 3. Therefore, they are indubitable.

Thus, from the simple Cogito ergo sum, we obtain certainty of several, viz, of Substance, mind, body, God, duration, order, number, modes, qualities, attributes, sensations, affections, appetites, magnitude, figure, color, pain

In this way we will observe, first of all, that we exist in so far as it is our nature to think, and at the same time that there is a God upon whom we depend; and after considering his attributes we will be able to investigate the truth of all other things, since God is the cause of them. Besides the notions we have of God and of our mind, we will likewise find that we possess the knowledge of many propositions which are eternally true, as, for example, that nothing cannot be the cause of anything, etc. We will farther discover in our minds the knowledge of a corporeal or extended nature that may be moved, divided, etc., and also of certain sensations that affect us, as of pain, colours, tastes, etc.

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1000+ YEARS BEFORE DESCARTES, SOME INDIAN PHILOSOPHERS USED SIMILAR REASONING TO ARRIVE AT A TOTALLY DIFFERENT CONCLUSION From the Dream and Waking state dilemma: ALL PERCEPTION OF THINGS IS FALSE (No Objects exist)

From the consciousness of the self: ONLY THE SELF IS REAL; EVERYTHING ELSE IS AN ILLUSION

This religious philosophical system is known as ADVAITA: Non-dualism (i.e. no subject-object distinction exists) Ultimate implication: All science and mathematics is a game of illusion. True knowledge is Self-realization.

DESCARTES HAD NO INTEREST IN ABSOLUTE SOLIPSISM He was interested in certainty of knowledge. He wanted to build knowledge block-wise and discovered the reliable foundations on which the building of knowledge can be constructed.

THE UNIVERSE IS MECHANICAL (OPERATED BY NATURAL LAWS)

MATHEMATICAL TRUTHS ARE AXIOMATIC

REASON IS RELIABLE

GOD EXISTS

I EXIST

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