Descartes’ Meditations

Meditation 1 was about ridding oneself of the beliefs that could be false, most notably from our senses and from our mental reasoning. Meditation 2 follows on that thread and is about finding beliefs that are true no matter what.

How does one find these propositions if we cannot trust our senses or reasoning? It was only from those propositions that you could build knowledge of the world that was reliable and true—only by working from a base of truth could you have the chance of concluding truth.

Obviously, the point was clear that he must attempt to find universal truths that were without a doubt correct. From this particular line of thought sprung one of the most famous lines in all of Western philosophy. But first, his inner dialogue:
But I was persuaded that there was nothing in all the world, that there was no heaven, no earth, that there were no minds, nor any bodies: was I not then likewise persuaded that I did not exist? Not at all; [surely] I myself did exist, since I persuaded myself of something. But there is some deceiver or other, very powerful and very cunning, who ever employs his ingenuity in deceiving me. Then without doubt I exist also if he deceives me, and let him deceive me as much as he will, he can never cause me to be nothing so long as I think that I am something. So that after having reflected well and carefully examined all things, we must come to the definite conclusion that this proposition, “I am, I exist,” is necessarily true each time that I pronounce it, or that I mentally conceive it.

You may have guessed what’s coming next. “I think; therefore, I exist”
In Latin, “Cogito ergo sum.”

This sprang from Descartes’ argument for a universal truth, winding its way around the first meditation’s two major roadblocks of not trusting senses and reasoning. The fact that he is being deceived by a demon is something in itself. If there is a deception, it must be acting upon something, and that something is Descartes himself. Thus, an undeniable truth must be that he exists.

Descartes realizes that he cannot question his own existence because he is a “thinking thing.” Even if he doubts the senses and the body, he cannot doubt himself because of his thoughts. Even if we were to be deceived by an evil demon as to what we see and hear, if the thoughts are still there, we would still exist.

But to further expound on what cogito ergo sum actually proves, it doesn’t mean that he exists as a person, a soul, or a body. It simply speaks to the limited scope that because he thinks, he exists, and thus the undeniable truth is only that he is a thing that thinks. Whatever thinks exists. Descartes thinks (albeit in a flawed way), and therefore he exists as a thinking thing.

It’s almost the mental equivalent of a tongue twister. At this point, all Descartes has reasoned out is that he exists as a thinking being and there are no other things he knows for certain—not his name, his age, or the size of his bed.

Where can we go from here?
Meditation 3

I am certain that I am a thinking thing; but do I not therefore likewise know what is required to render me certain of a truth? In this first knowledge, doubtless, there is nothing that gives me assurance of its truth except the clear and distinct perception of what I affirm, which would not indeed be sufficient to give me the assurance that what I say is true, if it could ever happen that anything I thus clearly and distinctly perceived should prove false; and accordingly it seems to me that I may now take as a general rule, that all that is very clearly and distinctly apprehended is true.

Translation? Well, Descartes sets a new standard for what could be considered true knowledge almost without us realizing it: “clearly and distinctly apprehended.” But what does that mean?

When we see something clearly, then our vision is unblocked—we have a clear view of the object in question. It is not too far away, it is not blurry, it is not too dark to make it out, and so on. When we see something distinctly, we are able to differentiate the object from all other objects. If we see a button among a pile of similar buttons, we do not see it distinctly—we can easily confuse it for one of the other buttons nearby.

In other words, clear and distinct perceptions are defined by Descartes as those perceptions that are so self-evident that, while they are held in the mind, they cannot logically be doubted.

Examples of clear and distinct perceptions include the propositions “A=A” and “I exist.” All knowledge, according to Descartes, is supposed to proceed from clear and distinct perceptions; no proposition is supposed to be judged as true unless it is perceived clearly and distinctly. Clear and distinct ideas are formally known as basic or self-justifying beliefs that Descartes hoped to use as foundations for his system of knowledge.

Consider the proposition that 2+3=5. We can have a clear understanding of the proposition (unobscured by other thoughts, with a clear understanding of the different parts of the proposition and how they fit together). Also, we aren’t going to confuse it with some other proposition (e.g., that 2+3=6).

You might feel that there are some gaps left in this definition of absolutely true knowledge, but that will be addressed shortly.

From what we know in Meditations on First Philosophy thus far, our senses and reasoning are unreliable, and then the only thing we can know is that we ourselves are a thing that thinks (because we are thinking right now). This allows us to infer that, since cogito ergo sum is clear and distinct, clear and distinct propositions are the base of true knowledge. Or does it?

How can we say that clear and distinct propositions are indeed the most basic truth that exists? How can we be prevented from going down a further rabbit hole when we know that our most basic thoughts and senses are unreliable? How do we know the demon can’t corrupt our thoughts on A=A?

This is where Descartes’ devout Catholicism comes into play, and perhaps he deviates from his stance of everything requiring hard evidence and proof. God is the ultimate arbiter of truth and knowledge. This is also one of the most common critiques of Meditations on First Philosophy, because it seems to be contradictory to the very point of not trusting your own beliefs or thoughts.

But when I considered any matter in arithmetic and geometry, that was very simple and easy, as, for example, that two and three added together make five, and things of this sort, did I not view them with at least sufficient clearness to warrant me in affirming their truth? Indeed, if I afterward judged that we ought to doubt of these things, it was for no other reason than because it occurred to me that a God might perhaps have given me such a nature as that I should be deceived, even respecting the matters that appeared to me the most evidently true…And in truth, as I have no ground for believing that Deity is deceitful, …the ground of doubt that rests only on this supposition is very slight, and, so to speak, metaphysical. But, that I may be able wholly to remove it, I must inquire whether there is a God…and if I find that there is a God, I must examine likewise whether he can be a deceiver; for, without the knowledge of these two truths, I do not see that I can ever be certain of anything.

Translation? Descartes is worried that there might be a demon who has the power to confuse us or deceive us even about a very simple mathematical proposition, so there is the possibility that we only think we are being clear and distinct.

Certain propositions (I doubt, I exist, I am a thinking thing) are completely demon-proof. However, he has said that even simple mathematical propositions are not. Thus, he uses God as a foil to keep the third meditation flowing. There are universal truths, espoused and approved by God, that we can find, and they are essentially categorized as clear and distinct. It’s arbitrary and not overly helpful in determining categories, but this does logically flow.

Anything that is not clear and distinct is said to be not demon-proof; thus, it cannot be absolute truth.

But if we get beyond the nitty-gritty details and steps of logic (some of it bordering on semantics and picking words apart), we are at the culmination of Descartes’ view of knowledge and the world. From this limited scope, he intended to engage in what is known as foundationalism—finding truths that are built only upon preceding truths.

It’s a way of looking at the world with absolute precision and skepticism. It’s how a scientist might approach a stringent test with multiple variables, yet it was his key to understanding knowledge.

We don’t have to approach life in such a systematic way, but we can certainly take some cues from Descartes about how to think and live better. Look before you leap, measure twice before cutting, and keep from jumping to conclusions. Challenge your thoughts, especially the ones that you consider engraved in stone. Don’t let yourself be guided by others just because. Have a high standard for what you believe; this ensures that your actions will represent exactly what you want.

Another famous philosopher known for his doubt and questioning methods, Socrates, once stated that the unexamined life is not worth living. Adhering to Descartes’ principles on doubt and truth will certainly get you into examining your life and gaining clarity into your own thoughts, desires, and motivations. That is perhaps the most powerful purpose of the chapter—if you don’t doubt your own thoughts (at least sometimes) then you are in a world of your own creation, and not one rooted in truth and reality.

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