de re/de dicto

de re and de dicto

By Dennis J. Darland

May 30, 2007

It has been pointed out to me (by Prof. Gregory Landini) that there is a connection between my ideas and the de re/de dicto distinction. I had heard of this distinction but never studied it.

My definition is at http://dennisdarland.com/philosophy/naming.html

I’ve read about de re/de dicto at http://en.wikipedia.org/wiki/De_dicto_and_de_re and http://plato.stanford.edu/entries/prop-attitude-reports/dere.html

I will try to apply my ideas to the cases presented there. My definition is basically of a de re belief (about objects) relation in terms of a de dicto belief (about symbols) relation and symbolic relations.

First the Stanford article motivates the distinction by the example:

(1) Ralph believes that someone is a spy.

This could mean either of the following.

(2) Ralph believes that there are spies

(3) Someone is such that Ralph believes that he is a spy.

(2) would be ($x) Ralph believes x is a spy.

(3) would be Ralph believes ($x) x is a spy.

On my definition (2) turns into ($x)($s)($w)(belief-R(Ralph,’[x/a]f(a)’,s,w,now) & propositional_formI(S,’[x/a]f(a)’,now) & Symbol-R(Ralph,s,spy) & Symbol-R(Ralph,w,x,now)

And (3) turns into ($s) Belief-R(Ralph,’($x)f(x)’,now) & propositional_form(S,’($x)f(x)’) & Symbol-R(Ralph,s,spy,now)

In these spy means what ‘is a spy’ means.

According to the Stanford article

A sentence is syntactically de re just in case it contains a pronoun or free variable within the scope of an opacity verb that is anaphoric on or bound by a singular term or quantifier outside the scope of that verb. Otherwise, it is syntactically de dicto.

Both of these are de dicto(about symbols) . But according to the Stanford article the first is syntactically de re.

The Stanford article then discusses another case where Ralph knows Orcutt under two guises – Mayor and a man in the dark.

(9) Ralph believes that he (pointing at the man in the dark) is a spy.

(10) Ralph believes that Mayor is a spy.

If (9) is true while (10) is false, the question arises whether Ralph believes Orcutt satisfies x is a spy.

On my definition of believes (the defined de re version of the relation) both of (9) and (10) are true and also Ralph believes Orcutt is a spy is true. (Appy the definition)

Also (again the defined de re version)

Ralph believes that he(pointing at the man in the dark) is not a spy.

And that the Mayor is not a spy

And that Orcutt is not a spy. (Again apply the definition)

But in the de dicto version which the de re version is defined in terms of:

(be careful not to miss the ‘~’ symbols for ‘not’)

Belief-R(Ralph,’f(x)’,’spy’,’the man in the dark’,now)

And

~Belief-R(Ralph,’~f(x), ‘spy’,the man in the dark’,now)

Also

Belief-R(Ralph,’~f(x)’,’spy’,’Mayor’,now)

And

~Belief-R(Ralph,’f(x)’,’spy’,’Mayor’,now)

If Ral;ph belief-R’s Mayor = Orcutt & Ralph is logical, he will have the same belief-R’s about the Mayor as about Orcutt.

Now the Stanford article defines:

A sentence is semantically de re just in case it permits substitution salva veritate. Otherwise, it is semantically de dicto.

Both my defined believes relation and the belief-R relation are semantically de re.