Simply Descartes

Kurt Smith

• Verlag: Simply Charly
• Jahr: 2018
• ISBN:
  9781943657346
• Thema: Filosofia
• Thema: Biografie in ambito filosofico

" Simply Descartes is the perfect one-stop-shop for all matters Cartesian. Smith presents Descartes's entire system from the ground up, building from metaphysics and epistemology to physics and morality. In some ways, he even goes one step further than the master himself for, with the benefit of hindsight and of the work of leading scholars, Smith reconstructs the system in a neat, orderly, clean and concise way, extracting the disparate pieces from Descartes's many works scattered over many years. For those seeking entry into Descartes, or into philosophy in general, as well as for those seeking a refresher on this foundational thinker, you can do no better than this book." —Andrew Pessin, author of The Irrationalist: The Tragic Murder of René Descartes and Professor of Philosophy at Connecticut College

René Descartes was born in La Haye en Touraine, France, on March 31, 1596. He attended a Jesuit college and studied law for two years, but he soon gave up formal academics to immerse himself in "the great book of the world." In 1618, he joined the army, where he became interested in military engineering and expanded his knowledge of physics and mathematics. Then, one night in 1619, he experienced what he described as divine visions, which inspired him to create a new mathematics-based philosophy. He spent the next 30 years writing a series of works that radically transformed mathematics and philosophy and, by the time of his death in 1650, he was recognized as one of Europe's greatest philosophers and scientists.

In Simply Descartes, Professor Kurt Smith offers the general reader an opportunity to get better acquainted with the philosophy of the man who, as much as any individual, helped shape our contemporary way of thinking. Written in simple, nonacademic language and based on the best recent scholarship, Simply Descartes is the ideal introduction to Descartes' life and work—from the famous Cogito ("I think, therefore I am") to the development of analytic geometry, to the nature of God.

Not to mention which, if you've ever wondered whether all living things are nothing more than fancy machines, or whether life is really a Matrix-like dream, you'll be amazed to discover that a 17th-century philosopher was asking (and answering) the same things!

3

The Search for Truth and Certainty

In this chapter, we will look more carefully at Descartes’s notions of truth, certainty, clarity and distinctness (and the latter’s counterparts, obscurity and confusion), as well as the compelling of the will.

The theory of truth that Descartes very likely inherited from his teachers was an Aristotelian correspondence theory of truth. We considered a version of this theory in Chapter 1. The basics of the theory tell us that truth arises as a certain relation holding between a proposition (or declarative sentence) and a fact. As was noted, the proposition is a linguistic entity; the fact is an ontological entity, a constituent of reality. When a proposition picks out a fact in all the right ways—that is, the proposition corresponds to a fact—the proposition is said to be true. In some of Descartes’s work, he seemed to have something like this in mind. But scholars find an alternate theory lurking about in the texts, which is based on Descartes’s talk of natures. These, as we’ll see, are not only the elements that constitute the essences of things, but also the inhabitants of the mind—they constitute the contents of our ideas. So, it looks like they play dual roles. Truth in this view is not something attributed to propositions, but to ideas, and in particular to the contents of our ideas. Talk of truth is related to those natures exhibited to us in or by way of our ideas.

Truth and Being

In Descartes’s view, when you clearly and distinctly perceive something, you are presented with something that is true. He also said that when we are aware of something that is true, we are aware of something that is real. “It is obvious,” he wrote, “that whatever is true is something.” (Fifth Meditation, AT VII 65; CSM II 45) As noted in Chapter 1, by “real” in this context Descartes meant that this something exists independently of his (or any finite) mind. Using Descartes’s more technical lingo, as he put it in his reply to Caterus, a real or actual thing possesses formal reality; insofar as it does, if this thing isn’t the mind itself (or one of its modes), it is something that exists independently of the mind. The upshot is that when clearly and distinctly perceiving something, one perceives something that is real, which, according to Descartes, is just another way of saying that one perceives something that is true.

This view looks like it might have its origin in the ancient Greek philosophers Parmenides and Plato, whose opinions were very different from the one that Aristotle would later hold. In short, Parmenides and Plato stated that there were two fundamental metaphysical categories: Being and Non-Being. Aligned with these were the epistemic categories of Truth and Falsity, and the moral categories of Good and Evil, respectively. In a letter to his friend and editor, Claude Clerselier, Descartes wrote that “Truth consists in being, and falsehood only in non-being.” (AT V 356; CSMK III 377) Earlier in the letter, he said, “[T]here is no distinction between truth and the thing or substance that is true…” (AT V 355; CSMK III 377) And, later in the letter, which we’ll discuss more fully in Chapter 6, he suggested that what is real is true, and these are coextensive with what is good. (AT V 357; CSMK III 378) Again, using Descartes’s technical terminology: true, real, and good are only conceptually distinct.

Natures: Simple and Composite

In Chapter 1, we briefly considered what Descartes referred to as simple natures. He used this phrasing in a very early work, Rules for the Direction of the Mind (c. 1628). We learned that extension is a simple nature, thinking is a simple nature, shape and size are simple natures, as are colors, smells, tastes, and so on. At the very least, they inhabit our ideas, as when you have, say, the idea of body, or the idea of mind, or the idea of God, or the idea of a triangle, or the idea of the Sun, or the idea of Pegasus. Although talk of such natures has its place in the metaphysics, in the Rules Descartes focused on their epistemic relationships—which natures are known in terms of which others. Such natures are also part of our current topic—Descartes’s epistemology.

In the Sixth Set of Replies, Descartes noted that there are two kinds of unity: unity by nature and unity by composition. (AT VII 423-424; CSM II 285-286) If analyzed properly, the idea of a body, he said, shows that its shape presupposes its being extended. In other words, the simple nature shape is shown to entail or to presuppose the simple nature extension. This is the sense in which something is a unity by nature. The idea of your doubting, for instance, shows that doubting presupposes thinking. So the simple nature doubting is shown to entail or to presuppose the simple nature thinking. Thus, the idea of a body and the idea of a mind, when properly analyzed, reveal things that are unities by nature.

Descartes considered someone who superficially reflects on his or her experience, where this person believes him or herself to be the very same thing that doubts and also walks (moves) from place to place. (AT VII 423-424; CSM II 285-286) What he or she fails to notice is that there is no entailment relation holding between doubting, say, and motion. Now, doubting entails thinking, not extension; and motion entails extension, not thinking. Descartes suggested that since no entailment relation is to be found in this person’s experience (no connection between thinking and being extended), the nature of this person as exhibited in this idea is not a unity by nature. It is what he called a unity by composition. This may be a real thing, but Descartes’s point was that since it is not revealed to be a unity by nature, it could easily turn out that this nature is not real in any sense that would allow it to exist independently of our idea. In any event, it would not be a nature about which we could have any knowledge, since nothing internal to the idea signifies its being unified (that is, no connection is seen).

The nature this person considers (namely, that he or she is a thing that both doubts and walks, say) could very well be something like the composite nature of Pegasus. As Descartes told Dutch theologian Frans Burman in an interview:

Even though we can with the utmost clarity imagine the head of a lion joined to the body of a goat, or some such thing, it does not therefore follow that they exist, since we do not clearly perceive the link, so to speak, which joins the parts together. (AT V 160; CSMK III 343-344)

The nature of body is a unity by nature, as is the nature of mind. But the nature of a human being, as suggested by the above analysis, is not a unity by nature but is a unity by composition. For, the idea of the human being seems to have the same defect as the idea of the lion-headed goat has, namely, it lacks the requisite entailment relations that would reveal the unity of its parts. So, although human nature may be real, we nevertheless cannot know anything about how it is unified.

It will turn out that we have lots of ideas about both kinds of unities. As for unities by nature, we have our ideas of body and mind, but all our ideas of geometrical shapes are also examples of such natures. And since these natures never change and are always the same, Descartes said that they should be called “immutable and eternal.” (AT VII 381; CSM II 262) Clearly, the adventitious (sensory) idea of the Sun would be like the above person’s idea of him or herself thinking and walking about. The shape of the Sun, for instance, entails extension (not thinking), and the heat (the sensible quality) exhibited in the idea entails thinking (not extension). But neither extension nor thinking entail one another. The Sun, according to this analysis, is not a unity by nature, but is a unity by composition—at least if we’re talking about the Sun that we sense. Contrast this with the astronomical idea of the Sun, which depicts an object that differs from the one we sense. This idea, for instance, exhibits the Sun as a spherically-shaped thing, in motion, much greater in size than the Earth, and so on. All other simple natures that don’t entail extension, like heat and color, have been removed. Here, the remaining simple natures shape, motion, and size entail or presuppose the simple nature extension. Thusly conceived, this nature, which may be better understood simply as the nature of a body, is a unity by nature.

Unities by nature are real. By contrast, unities by composition may or may not be real. Since unities by nature are real, the simple natures that make them up are real too. What is interesting here is that even though a unity by composition may not be real, the simple natures that make it up are nevertheless real. Descartes suggested something like this in the First Meditation, when noting the difference between the things we may experience in dreams versus the things we sense when awake. He said that even though what we may dream about may not be real, the items the mind employs to fabricate those things (the “things” presented in the dream) must be real. (AT VII 20; CSM II 13-14) The items he specifically mentioned are colors, which we know from what he had said in the Rules are simple natures. Here, to use our new jargon, the things experienced in dreams may be unities by composition. And, for all we know, much of what we sense may be too. Be that as it may, it seems to be Descartes’s view that all simple natures are real, regardless of whether they make up a unity by nature or a unity by composition. They are kind of like “atoms,” where they serve as underlying conditions for our having any experience of the world. Given the connection between real and true, then, it follows that all ideas that exhibit unities by nature, insofar as they show things that are real, are true. The line of reasoning can go the other way, too—namely, given the connection between real and true, it follows that all ideas that are true exhibit things that are real.

Clarity and Distinctness

In Chapter 2, we mentioned clarity and distinctness. These were important notions for Descartes. Ideas that are clear and distinct, he said, are true. (Third Meditation, AT VII 35; CSM II 24) And we now know that in his view, whatever is true is something (real). So, clear and distinct ideas are ideas of real things (actual things, things that possess formal reality).

Descartes never really defined “clarity,” at least not cleanly enough to avoid criticism. For example, in the Principles, he simply wrote that “I call a perception ‘clear’ when it is present and accessible to the attentive mind.” (AT VIIIA 21; CSM I 207) In other places, he posited that clarity emerges when we have an immediate insight into a connection between the simple natures exhibited in an idea. (AT V 160; CSMK III 343-344) This connection cannot be contingent, but will be necessary. The necessity of the connection is understood, as noted above, in terms of entailment or presupposition (though, as we’ll see shortly, the insight is best expressed by the latter). He again presented the example of the simple natures shape and extension: their connection is shown to be necessary insofar as we cannot conceive shape independently of extension. This is another way of saying that the simple nature shape presupposes extension. (Rules, AT X 421; CSM I 45-46, see also Principles, AT VIIIA 25; CSM I 210) We might take this to mean that the idea exhibiting the simple nature shape also shows the simple nature extension, whether we were initially aware of this necessity or not. But once we “see” this connection between them, the idea is said to be clear (or at least to be clearer than before). Whenever the necessary connection is absent, the idea is said to be obscure. The connection is either not there or is being “obscured” by some other elements (simple natures) that constitute the content of the idea. Clarity and obscurity are at opposite ends of the spectrum, so to speak. The clearer an idea, the less obscure it is; and the more obscure, the less clea...

Inhaltsverzeichnis

• Cover
• Title Page
• Copyright
• Table Of Contents
• Praise for Simply Descartes
• Other Great Lives
• Series Editor's Foreword
• Preface
• Acknowledgements
• Descartes’s System: The Big Picture
• Mind
• The Search for Truth and Certainty
• Body
• Physics and the Mechanization of Life
• Human Beings
• Descartes's Legacy
• Suggested Reading
• About the Author
• A Word from the Publisher