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Anselm & Aquinas

Anselm & Aquinas. December 23, 2005. Anselm of Canterbury (1033-1109 AD). The Ontological Argument for the Existence of God. (Text, pp. 263-4). Credo ut intelligam (“I believe that I might understand”). The relationship between faith and reason (Faith must precede understanding?).

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Anselm & Aquinas

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  1. Anselm & Aquinas December 23, 2005

  2. Anselm of Canterbury(1033-1109 AD) The Ontological Argument for the Existence of God (Text, pp. 263-4)

  3. Credo ut intelligam(“I believe that I might understand”) The relationship between faith and reason (Faith must precede understanding?)

  4. Why is the ontological argument called “ontological”?

  5. What is the “ontological reference” of the word “God”? That is, what kind of being does the word “God” refer to? According to Anselm, the word “God” refers to “something than which nothing greater can be thought of.”

  6. Necessity & contingency (again) • Necessarily true statements (tautologies) cannot be false, and necessarily false statements (contradictions) cannot be true. • Contingent statements can be either true or false, depending on facts, evidence, & circumstances.

  7. Necessary beings(i.e., things with necessary existence) cannot not-exist. Impossible beings (i.e., things whose existence is contradictory, e.g., round squares) cannot exist.

  8. Contingent beings(i.e., beings whose existence and nonexistence are neither necessary nor impossible) • may exist (rocks) • or not (unicorns). • Their existence is (logically) possible, • and their nonexistence is also (logically) possible.

  9. Is it logically possible for the existence of “something than which nothing greater can be thought of” to be contingent? More precisely, is the nonexistence of “something than which nothing greater can be thought of” logically possible?

  10. Anselm’s “1st” ontological argument (Text, pp. 263-4) 1. Something than which nothing greater can be thought of cannot exist only as an idea in the mind because, in addition to existing as an idea in the mind, it can also be thought of as existing in reality, that is, objectively, which is greater than existing only as an idea in the mind. Ifsomething than which nothing greater can be thought of exists only as an idea in the mind, then “that than which something greatercannot be thought of” is “that than which something greatercan be thought of,” which is impossible because it is self-contradictory. Something than which nothing greater can be thought of must exist, not only as an idea in the mind, but in reality. 2. 3.

  11. In other words, A God that actually exists is greater than a “God” that exists only as an idea in the mind. If “God” exists only as an idea in the mind, then “God” is “not-God” (because something that exists only as an idea in the mind is not “something than which nothing greater can be thought of”). Thus, the claim that God does not actually exist implies a contradiction and is therefore necessarily false. If the claim that God does not actually exist is necessarily false, then the claim that God actually exists is necessarily true (because the negation of a contradiction is a tautology). 1 2 3 4

  12. So God must exist,and atheism must be false, right?

  13. Anselm’s “2d” Ontological Argument (Text, p. 264) 1. It is possible to think of something that cannot be thought not to exist [that is, anecessary being]. A necessary being [something that cannot be thought not to exist] would be greater than something thatcan be thought not to exist [that is, acontingent being]. Ifsomething than which nothing greater can be thought ofcould be thought of as not existing, thensomething than which nothing greater can be thought of would not besomething than which nothing greater can be thought of, which is an outright contradiction and thus absurd. Something than which nothing greater can be thought of has such a high degree of existence, that is, necessary existence, that it cannot be thought of as not existing, that is, its nonexistence isimpossible. 2. 3. 4.

  14. In other words, • It is possible to think of a necessary being, i.e., a being whose nonexistence is impossible. • Necessary existence is greater than contingent existence, and a necessary being is greater than a contingent being. • If the nonexistence of God is possible, then God must be a contingent being. But then “God” would be “not-God” because a contingent being cannot be “something than which nothing greater can be thought of.” • Thus, the claim that God’s nonexistence is possible implies a contradiction and is therefore necessarily false. • If the claim that God’s nonexistence is possible is necessarily false, then the claim that God’s nonexistence is impossible is necessarily true (because the negation of a contradiction is a tautology).

  15. So God’s nonexistence is impossible,and therefore God must exist.Thus, agnosticism must be false too, right?

  16. Furthermore, God is the ONLY BEING whose nonexistence is logically impossible. (That is, no other being deserves the title of “something than which nothing greater can be thought of.”)

  17. The existences of all other beings(actual or conceivable)are either contingentor impossible.

  18. How can “the fool” doubt or deny the existence of God? Anselm’s answer: The “fool” (i.e., the atheist or agnostic) does not understand the true meaning of “something than which nothing greater can be thought of.”

  19. Thomas Aquinas(1224-1274 AD) on the existence of God (Text, pp. 265-8)

  20. Aquinas’s three main points • The existence of God is not self-evident (to the human mind) (Text, pp. 265-6). • Although the existence of God is not self-evident, it can be proved by reasoning from effect to cause (Text, pp. 266). • There are five proofs of God’s existence (Text, pp. 266-8).

  21. Aquinas’s 1st argument: change 1. Some of the things in the world are changing. 2. Whatever changes must be caused to change by something other than itself. 3. If anything that causes change must itself be changing, then it also must be caused to change by something other than itself, and that cause must also be caused by still another cause, and so on [to infinity]. 4. This process of cause and effect cannot go on to infinity because, if it did, there would be no first cause of change and thus no later causes of change (since later causes of change are merely the effects of a first or primary cause -- for example, a stick can move something only if the stick is moved by a hand). 5. There must be a first cause of change, which itself is not caused or changed by anything, and this everyone understands to be God. [What about human beings? Determinism?] [Infinite regress] [“A” first cause? God?]

  22. Critical Questions on Aquinas’s 1st Argument(Think carefully about the following questions.) • The 2d premise: Doesn’t it imply determinism? Doesn’t it rule out human freedom? • The inference: Even if the argument proves the existence of an uncaused first cause, does it prove that there is only one such originating cause? Might there not be more than one? And even if the argument proves that there is just one first cause, is Aquinas entitled to say that it is “God”? What are the various attributes of “God”? Must a first cause have all of those attributes?

  23. Aquinas’s 2d argument: causation 1. In the world that we perceive with our senses, we find a series of causes. 2. Nothing can be the cause of itself [i.e., of its own existence], for then it would be prior to itself, which is impossible. 3. It is also impossible for a series of causes to go on to infinity. In every series of causes, the first cause produces one or more later causes, and the later causes produce the last event in the series. If a cause were removed from the series, so would its effect be removed. So if there were no first cause [in a series of causes], that is, if the series went on to infinity, there could be no later causes and no last event in the series. 4. It is obvious that there are such causes and events. 5. There must be a first cause, which itself is not caused by anything, and this everyone understands to be “God.” [“A” first cause? God?]

  24. Critical Questions on Aquinas’s 2nd Argument(Think carefully about the following questions.) • How does A’s 2nd argument differ from his 1st? (The 1st looks at change from the standpoint of effects, and the 2nd looks at change from the standpoint of causes. Do you see that? The two arguments are not exactly the same.) • The inference: Same questions as on the 1st argument. Even if the argument proves the existence of an uncaused first cause, does it prove that there is only one such originating cause? Might there not be more than one? And even if the argument proves that there is just one first cause, is Aquinas entitled to say that it is “God”? What are the various attributes of “God”? Must a first cause have all of those attributes?

  25. Aquinas’s 3d argument: contingency & necessity 1. There are things that can either exist or not [that is, contingent beings], which is clear from the fact that some things come into being and later pass out of existence (that is, they exist at some times but not at others). 2. Something like this [a contingent being] cannot always exist because something whose nonexistence is possible must have not-existed at some time. 3. If everything can not-be [that is, if everything has contingent existence], then at some time before now there would have been absolutely nothing in existence. 4. If there were ever nothing in existence, then even now there would be nothing in existence because something that doesn’t exist can begin to exist only if it is brought into existence by something already existing. If at some time before now there was nothing in existence, it would have been impossible for anything to begin to exist, and there would be nothing existing now, which is obviously false 5. It can’t be that everything’s existence is merely possible [contingent]. There must be something that has necessary existence. 6. There is a being that exists necessarily, and this everyone calls “God.” ? ? [“A” necessary being? God?]

  26. Critical Questions on Aquinas’s 3rd Argument(Think carefully about the following questions.) • 2nd premise: Are there any reasons to doubt the truth of this premise (which assumes that a contingent being must come into existence)? • 3rd premise: Are there any reasons to doubt the truth of this premise? Like the 2nd premise, the 3rd premise assumes that contingent beings must come into existence. If that is true of one contingent being, then (Aquinas reasons) it must be true of all of them together. Thus, if all things now existing are contingent, then they all must have come into existence before now; and if there is no necessary being, then at some time before now there must have been nothing (absolutely nothing) in existence. Is there any way around that? • The inference: Even if the argument proves the existence of an uncaused first cause that is a necessary being, does it prove that there is only one such originating and necessarily existing cause? Might there not be more than one? And even if the argument proves that there is just one necessarily existing first cause, is Aquinas entitled to say that it is “God”? What are the various attributes of “God”? Must a necessarily existing first cause have all of the divine attributes?

  27. Aquinas’s 5th argument: natural order & design 1. Look at the way things happen in the world. Even things that lack consciousness, such as physical objects, tend toward an end. In fact, they always (or almost always) behave in such a way as to produce what is best [with regard to the natural order]. 2. Things in nature reach their end, not by chance or accident, but by design. 3. Anything that lacks consciousness can tend toward an end [or follow a design] only if it is directed to do so by some other being that is conscious and intelligent (as an arrow is directed toward a target by an archer). 4. There is some intelligent being who directs all things in nature toward their end, and this being we call "God." In other words,

  28. (Simplified Version) • There is evidence of intelligent design in nature. • Where there is (evidence of) intelligent design, there must be an intelligent designer. • There is an intelligent designer of nature • (& it is God). 1. 2. 3. Critical Questions: 1. Is there? Isn’t there also a lot of disorder in nature? 2. Must there be? Appearance vs. Reality. Why can’t the “order” and “design” of nature be accidental, a product of chance? 3. “An” intelligent designer? Why not more than one? Why must it be “God”?

  29. Aquinas’s 4th argument:gradations of value Can this be false? 1. Some things are better than other things. 2. Something can be “better” or “worse” than something else only if it is closer to or further away from that which is best [that is, perfect]. 3. That which is best [that is, perfect] must exist, and this must be the greatest conceivable being, that is, God.

  30. Critical Questions on Aquinas’s 4th Argument • Do you disagree with the 1st premise? Why? If you disagree with the 1st premise, then it is your view that nothing is better than anything else (see next slide). • Do you disagree with the 2nd premise? Why? Can anything be (really) better than anything else in the absence of an actually-existing perfection? • Is the argument valid? Yes, it is. So if the premises are true, then it necessarily follows that the conclusion is true. In this case (if the argument is sound), Aquinas really does prove the existence of “God” (a perfect being). Do you see that? A perfect being would possess all divine attributes, and there cannot be more than one perfect being. Do you see why?

  31. Theories that hold that nothing is really better than anything else: • Axiological subjectivism (vs. objectivism) • Axiological relativism (vs. absolutism) • Axiological nihilism (vs. essentialism?) • Axiological non-cognitivism (skepticism) (vs. cognitivism) What are these theories? You might find it interesting to research them on your own. Which (if any) of them do you subscribe to? Why? (This NOT for extra credit. There are no extra credit opportunities in this course.)

  32. That’s all for now . . . .

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