2.1: The Ontological Argument and The Lost Island Objection (St. Anselm and Gaunilo of Marmoutiers)

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8 The Ontological Argument and The Lost Island Objection
St. Anselm and Gaunilo of Marmoutiers^¹³

Anselm’s “Ontological Argument”^¹⁴

Therefore, Lord, you who give knowledge of the faith, give me as much knowledge as you know to be fitting for me, because you are as we believe and that which we believe. And indeed we believe you are something greater than which cannot be thought. Or is there no such kind of thing, for "the fool said in his heart, 'there is no God'" (Ps. 13:1, 52:1)? But certainly that same fool, having heard what I just said, "something greater than which cannot be thought," understands what he heard, and what he understands is in his thought, even if he does not think it exists. For it is one thing for something to exist in a person's thought and quite another for the person to think that thing exists. For when a painter thinks ahead to what he will paint, he has that picture in his thought, but he does not yet think it exists, because he has not done it yet. Once he has painted it he has it in his thought and thinks it exists because he has done it. Thus even the fool is compelled to grant that something greater than which cannot be thought exists in thought, because he understands what he hears, and whatever is understood exists in thought. And certainly that greater than which cannot be understood cannot exist only in thought, for if it exists only in thought it could also be thought of as existing in reality as well, which is greater. If, therefore, that than which greater cannot be thought exists in thought alone, then that than which greater cannot be thought turns out to be that than which something greater actually can be thought, but that is obviously impossible. Therefore something than which greater cannot be thought undoubtedly exists both in thought and in reality.

Gaunilo’s “Lost Island Objection”

For example, they say there is in the ocean somewhere an island which, due to the difficulty (or rather the impossibility) of finding what does not actually exist, is called "the lost island." And they say that this island has all manner of riches and delights, even more of them than the Isles of the Blest, and having no owner or inhabitant it is superior in the abundance of its riches to all other lands which are inhabited by men. If someone should tell me that such is the case, I will find it easy to understand what he says, since there is nothing difficult about it. But suppose he then adds, as if he were stating a logical consequence, "Well then, you can no longer doubt that this island more excellent than all other lands really exists somewhere, since you do not doubt that it is in your mind; and since it is more excellent to exist not only in the mind but in reality as well, this island must necessarily exist, because if it didn't, any other island really existing would be more excellent than it, and thus that island now thought of by you as more excellent will not be such." If, I say, someone tries to convince me though this argument that the island really exists and there should be no more doubt about it, I will either think he is joking or I will have a hard time deciding who is the bigger fool, me if I believe him or him if he thinks he has proved its existence without having first convinced me that this excellence is something undoubtedly existing in reality and not just something false or uncertain existing in my mind.

For Review and Discussion:

1. Lay out the argument that Anselm presents in standard logical form. Is it valid? Do the same with Gaunilo’s. Is it valid? Do the two arguments have the same structure?

2. Which part of Anselm’s argument requires the most defense. Do you think he’s correct in his view?

3. Gaunilo believes his argument functions as a type of reduction ad absurdum response to Anselm’s argument by showing that his reasoning will lead to absurd conclusions. Do you think Gaunilo’s response works?