## Sunday, May 20, 2012

### Another version of the circularity argument

Jason has questioned which argument of Bill's I am talking about. I did link to one version of the argument (I have been involved with many over the years). But I found another one here, slightly longer. Bill says:
Now either x exists or it does not.

Suppose it does not. Then we have instantiation without existence. If so, then existence cannot be instantiation. For example, let C be the concept winged horse and let x be Pegasus. The latter instantiates the former since Pegasus is a winged horse. But Pegasus does not exist. So existence cannot be the second-level property of instantiation if we allow nonexistent objects to serve as instances of concepts.

Now suppose that x exists. Then the theory is circular: it presupposes and does not eliminate first-level existence. The concept blogging philosopher is instantiated by me, but only because I possess first-level existence. One cannot coherently maintain that my existence consists in my instantiating that concept or any concept for the simple reason that (first-level) existence is what makes it possible for me to instantiate any concept in the first place.
I follow the first leg of the argument. If there are non-existent objects, then existence obviously cannot boil down to instantiation. That is very clear. It is the second leg which makes no sense. The argument seems to be that some philosopher is blogging, only because a blogging philosopher exists. Therefore the existence of a blogging philosopher cannot boil down to some philosopher being a blogger.

One might as well argue that this meat being lamb cannot boil down to this being mutton, for it is lamb because it is mutton. Therefore the definition 'mutton is lamb' is circular. But that argument is blatantly bad.

Anthony said...

I think the argument is that existence is being defined in terms of instantiation, and that instantiation is being defined in terms of existence. This is what is circular. (As would defining lamb as mutton, and mutton as lamb.)

One way around this is to say that the two uses of "existence" are different. Existence, as in "blogging philosophers exist", is instantiation. But existence, as in "Bill Vallicella exists", is something else.

Bill, of course, would then ask what that "something else" is. And then, when presented with the answer, would object to it. But I don't think his objection be that the definition is circular.

Edward Ockham said...

>>I think the argument is that existence is being defined in terms of instantiation, and that instantiation is being defined in terms of existence. This is what is circular. (As would defining lamb as mutton, and mutton as lamb.)

How is instantiation being defined as existence? The assumption is that instantation is primitive and cannot be further defined. Obviously not everything can be defined, otherwise we would be going to infinity.

Edward Ockham said...

>>But existence, as in "Bill Vallicella exists", is something else.

Now you come to the singular term argument. But that is a separate argument.

Anthony said...

How is instantiation defined as existence? This is explained in part in the paragraph you left out, before the start of your quote.

Instantiation, he says, is instantiation of something that exists. Note that I am not necessarily agreeing with this. O would be interested in hearing what you think of that paragraph which you omitted.

You say that instantiation is primitive and can't be further defined. You also say that obviously not everything can be defined. But this seems to contradict your earlier statement that a definition is just using different words. Can I define lamb as mutton, and mutton as lamb? Both definitions use different words.

Edward Ockham said...

>>How is instantiation defined as existence?

As explained in my original post:

An American philosopher exists = (def) the concept "American philosopher" is instantiated.

>>Instantiation, he says, is instantiation of something that exists.

Yes. But that does not prove the definition is circular, unless it can be shown that 'exists' adds something to the concept of 'something that is instantiated'.

>>You say that instantiation is primitive and can't be further defined. You also say that obviously not everything can be defined. But this seems to contradict your earlier statement that a definition is just using different words.

You are eventually going to run out of words.

Anthony said...

>> But that does not prove the definition is circular, unless it can be shown that 'exists' adds something to the concept of 'something that is instantiated'.

Well, maybe he didn't *prove* the definition is circular. But this seems to be what he is getting at.

>> You are eventually going to run out of words.

Not if you allow circles such as defining lamb as mutton and defining mutton as lamb.

You said "A circular definition is one where the left hand term, the term to be defined, the definiendum, contains a term or a word that is also contained in the defining expression, the definiens."

"Mutton is defined as lamb". "Lamb is defined as mutton". Are these definitions? Are they circular?

Edward Ockham said...

>>Not if you allow circles such as defining lamb as mutton and defining mutton as lamb.

I think that's a very good point. On my definition of 'circular definition', neither of the two definitions "mutton is lamb" and "lamb is mutton" are circular on their own. But they clearly are circular, taken together.

So I have failed to establish that the thin conception is not circular. On the other hand, Bill has not established that it is circular. At least not to my mind. He would argue that it is self-evident.

David Brightly said...

Could Bill be saying something like this? We all know what we mean by 'Socrates exists' even if the only way we can express this thought is by repeating the sentence. Instantiation, however, seems metalinguistic: we would say something like 'Frodo instantiates the concept Hobbit', and in doing so we introduce the name 'Hobbit' to stand for an object of a new kind that our ordinary everyday speech doesn't have. In Quine-speak we can now quantify over ordinary objects plus concept objects. Indeed, we can conceive of someone getting by in the world without the concept Concept at all, ie, without uttering sentences that mention concept words in addition to those that use them. So our understanding of instantiation is not primary---it rests on our understanding of ordinary level language that includes 'exists'. Hence to define 'exists' in terms of 'instantiates' is to put the cart before the horse.

Edward Ockham said...

>>Instantiation, however, seems metalinguistic

The problem is that Bill's argument applies equally to the definition of 'An American philosopher exists' as 'some philosopher is American', which does not employ the Fregean baggage of 'concepts'.

David Brightly said...

Que? From Thin existence and circularity:

1. An American philosopher exists
2. The concept 'American philosopher' is instantiated
3. There is an American philosopher
4. Some philosopher is American

Maverick, as I understand him, believes that this equivalence involves a circularity. I.e. The definition of the first statement in terms of the second (and probably the third or the fourth, though he has never said this) is circular. What does he mean?

So, concentrating on (1) and (2) we are clearly dealing with the Fregean baggage surrounding 'instantiation', which occurs in both legs of Bill's argument currently being commented on.