The major premises in Descartes' Third Meditation are his degrees of reality principle and his causal adequacy principle. Descartes' degrees of reality come from his ideas of more or less real, things can fall under properties being less real, like colors, to finite substances, to infinite substances being the most real, like God "But I understand God to be actually infinite, so that he can add nothing to His supreme perfection" (Third Meditation, pg 17). Something like a table can be a finite substance but the color of the table, its brownness, is something considered to be less real to Descartes, a less real property. Descartes' casual adequacy principle which goes like "Now it is manifest by the natural light that there must be as much reality in the efficient and total cause as in its effect," (Third Meditation, pg 15) meaning that something is not created from nothing, like the stone. The casual adequacy principle can
By saying this he means that a formal reality is expressed as an infinite substance, finite substance, or finite mode. And by objective, we are talking about ideas or representations that we have of these finite substances, infinite substances, and finite modes. One could theoretically be producing these ideas, but Descartes dismisses this possibility for two reasons; first, that the idea of corporeality does not presuppose thought and second, that our will seems to have no effect on what we perceive or don't perceive. He believes this because the scope of the will is wider than that of the intellect. Therefore, turning aside from making any judgment where one is at all questioning causes the correct behavior and avoids any error.
Descartes separates his notion of ideas in two categories: the formal or material and objective. The formal and material notion is that all ideas are the same. The objective notion is that all ideas are different. Considered formally, ideas are the content of the activity of thinking and involved in the cogito. These ideas are clear and distinct. When ideas are considered objectively, on the other hand, they are the mental representatives of things that really exist. Therefore, the connections between ideas yield truths when they correspond to the realities of the world in which we live. Ideas do not come from experience, but are found within intellect itself. Descartes, however, states that these clear and distinct ideas do not necessarily correspond to realities, as there may be an omnipotent deceiver.
Descartes’ method offers definitive conclusions on certain topics, (his existence, the existence of God)but his reasoning is not without error. He uses three arguments to prove existence (His and God’s) that attempt to solidify his conclusions. For his method to function seamlessly, Descartes needs to be consistent in his use of the method, that is, he must continue to doubt and challenge thoughts that originate in his own mind. He is unable to achieve this ideal state of mind, however, and his proofs are shown to be faulty.
The second argument that Descartes defends is another question posed towards the senses. How can we take anything as real if our dreams cannot be
Descartes’ skeptical arguments begin from the thought that everything can be doubted; the first being our senses. He claims that our senses can sometimes deceive us (e.g. when viewing things from far away). Things that can deceive us once, have the possibility to be deceiving us all the time—giving us reason to doubt all sensory claims. This leads to a problem since humans rely on empirical knowledge. If one cannot consider any claim delivered by sense to be true knowledge, then it gives reason for one to doubt reality. Following is the dream argument in which what seems to be tangible reality, is an effect of a dreaming experience. Descartes gives the example of dreaming he is sitting by a fire when in actuality he could be asleep
Descartes argues that some ideas are more real than others. These ideas are those that represent substances and contain more objective reality. These ideas are first modes or accidents, finite substance, and infinite substance. Descartes
Descartes is considering that all of his experiences could be false and that everything is just the invention of a powerful being. This resulted in this argument:
As with almost all of Descartes inquiries the roots of his second argument for the existence of God begin with his desire to build a foundation of knowledge that he can clearly and distinctly perceive. At the beginning of the third meditation Descartes once again recollects the things that he knows with certainty. The problem arises when he attempts to clearly and distinctly understand truths of arithmetic and geometry. Descartes has enough evidence to believe these things, but one major doubt is still present; the possibility of God being a deceiver. Descartes worry is that all the knowledge that he possesses through intuition could potentially be false if God merely chooses to deceive him. So in order to have a clear and distinct perception of arithmetic truths (and other such intuitive truths) Descartes delves into the question of God’s existence (and whether this God could be a deceiver or not).
Firstly, Descartes deals with the issue of empiricism- the theory that our knowledge is derived from our sensory experiences. Since we know from everyday errors that our senses have the ability to deceive us fairly often so making our perceptions to be something that it is not. For example, there are lots of examples of optical illusions and the fact that the train tracks may appear to converge from a distance. Consequently, we ought to
Descartes is able to examine ideas and gain knowledge form them. Innate ideas mean they are present at birth, in other words we are implanted with certain ideas at our creation. He often uses ‘innate ideas’ to explain the mind’s original programming. “An infant’s mind is programmed with the rules of logic. Consider as an example the valid rule, modus ponens. Let P and Q stand for variables… the rules states that, if P then Q is true and P is true, then it follows that Q is true. We know that we are programmed with this rule because young children, who have never studied logic and have never entertained the rule, when given an argument in which the variables above are replaced by actual sentences, are able to intuit the validity of the argument.” Descartes believed our minds are programmed with eternal truths, “Whatever comes into existence must have been brought into existence by something else.” He also discovers that the idea of God is only part of his initial programming but also that God, operating through secondary sources such as his parents, is the programmer.
Descartes utilizes another rule in his thought process which states that objective reality cannot exist without formal reality. By this he means that we cannot form an idea without a cause. Assuming that God does exist would be an example of a Formal reality. Whereas the idea of God, is considered objective reality because it represents an infinite substance. Ideas themselves automatically have objective reality because the idea itself represents some reality. Also, the more perfect ideas cannot come from the less perfect; this is called The Causal
Given the above arguments one can begin to understand the nature of the God Descartes is endeavoring to prove. For Descartes, God is infinite and perfect existence. God is “eternal, immutable, independent, supremely intelligent, supremely powerful, and [the creator of] everything else". (Descartes 20) Not only does God possess this nature but it is necessary that He does so. If God is not infinite or perfect God could not exist as these attributes are essential to God's existence. Furthermore, if God is not the ultimate creator the innate idea of God we experience would cease to be innate but adventitious (externally caused) or imaginative (caused by the mind) which is again impossible given its content. Given these qualities one can draw a connection to the
He reasons that, through these principals, his idea of God cannot have come from himself, as he is an imperfect being. He does not have the capability of thinking of an infinite substance or a perfect substance, such as God, because he has lesser reality than these ideas and cannot be the cause of them. The only way these ideas could exist is if they were created by something of equal (greater being impossible, as infinite perfection cannot have a superior) reality. Because God is the only infinite Descartes can recognize at this state, it must be God that planted the idea in his mind.
Descartes’ Meditations on First Philosophy (1641) contains six Meditations. In the first two of these Descartes addresses doubt and certainty. By the end of the second Meditation Descartes establishes the possibility of certainty by concluding that he is a “thinking thing” and that this is beyond doubt. Having established the possibility of certainty, Descartes attempts to prove the existence of God. The argument he presents in the Third Meditation for the existence of God has been nicknamed the ‘Trademark’ argument. This argument deals with types of ideas, of which there are three, a principle called the Causal Adequacy principle, and a sliding scale of reality. The argument concludes that the idea of a God that is a perfect being is an innate idea that is real and was caused by God and therefore God is real. This argument will be explained with the greater detail in the next paragraph. In the Fifth Meditation Descartes again addresses the existence of God with an argument for His existence. This argument is a variation of St. Anselm’s ontological argument. This argument is also framed around his theory of ideas, as well as his principle of ‘clear and distinct perception’ and is explained and discussed in paragraph three. The paragraphs following these will discuss how convincing these two arguments from Descartes are and will deal with various objections. Many of these objections are strong enough that it will be clear why Descartes’ case has failed to convince everyone.