Philosophical Devices
Week 5 – Naming & Necessity
--------------------------------------------------------------------------------------------------------FROM LAST WEEK:
SOME BRIEF ISSUES CONCERNING ESSENTIAL PROPERTIES
The intuitive notion of ‘essential property’ is a property that characterizes an object, which is
part of the object’s metaphysical nature.
Two major questions crop up regarding essential properties.
First is the ‘Analysis Question’ – recall our two definitions
 Essential property: A property P is essential to an object o iff necessarily, if o exists,
then o has P
 Accidental property: A property P is accidental to an object o iff possibly, o exists and
fails to have P
Not everyone thinks the above definitions are suitable to capture this intuitive idea anymore,
mostly due to a series of counter-examples offered by Kit Fine:
(1) Necessity, if Socrates exists, then he has the property of being such that there are
infinitely many prime numbers. Intuitively, however, this property isn’t essential to
Socrates – after all, what does his nature have to do with how many primes there are?
(2) Necessarily, if Socrates exists, then he has the property of being such that,
necessarily, if the Eiffel Tower exists, then it is a Tower. But what does the Eiffel
Tower and its nature have to do with Socrates and his?
(3) Necessarily, if Socrates exists, then he exists. But Socrates isn’t a special ‘Essential
being’, whose essence includes his own existence!
(4) Necessarily, if Socrates exists, then he is a member of {Socrates}. But what do sets
have to do with the essences of people? While it might be true that {Socrates}
essentially has Socrates as a member, it certainly isn’t true the other way around!
We therefore get the Analysis Question: what is the proper way to define ‘essential property’?
The second question is one that Papineau mentions briefly, but will discuss more in the next
chapter. Specifically, it asks, ‘Given a particular object, what properties are essential to it?’
More generally, we can understand this question to be aimed at trying to determine what
properties are essential. Since this concerns the extension of the predicate ‘is essential’, it
seems natural to call this the Extension Question.
Note that (a) these two questions can (and frequently do) come apart, and (b) they are still
tightly bound up with the above questions concerning possible worlds/modality
--------------------------------------------------------------------------------------------------------SCOPE DISTINCTIONS
(1) ‘Every philosopher favours a distinction’
This is ambiguous between two very different readings.
(1’) For every philosopher, there is a distinction they favour
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Necessity & Possible Worlds
The truth of (1’) is compatible with the favoured distinctions being different for different
philosophers – I might favour the Essential/accidental distinction, Prof. Schnieder the
Analytic/synthetic, etc.
(1*) There is a specific distinction that every philosopher loves
The truth of (1*) isn’t compatible with the favoured distinctions being different, since it
entails that there is a single distinction that all philosophers favour.
The difference between the two readings is the scope assignment of the quantifiers; in (1*),
the existential quantifier for the distinction has wide scope, while in (1’) it has narrow scope.
Another, hopefully familiar case of scope ambiguity:
(2) The Present King of France is not bald
(2’) NOT (The Present King of France is bald)
(2*) The Present King of France is (not bald)
The truth of (2’) doesn’t require the existence of the PKoF, while (2*)’s truth does.
--------------------------------------------------------------------------------------------------------RIGID VS NON-RIGID DESIGNATORS
According to Kripke, the function of a proper name is to pick out an individual. Importantly,
proper names do NOT convey any descriptive content – they simply refer!
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E.g. ‘The Holy Roman Empire’ is a proper name, and it refers to a particular (now
non-existent) political state. However, this state was neither Holy, nor Roman, nor an
Empire.
Upshot: when they appear in statements, proper names make scope ambiguity disappear. E.g.
there is no difference between Necessarily, a is identical to a and a necessarily is identical to
a.
Rigid designator: a term t is a rigid designator iff it refers to the same thing in all possible
worlds in which that thing exists, and nothing in those worlds in which the thing does not
exist.
Persistently rigid: a term t is persistently rigid iff it designates the same thing in every
possible world in which that thing exists and designates nothing in all other possible worlds.
Obstinately rigid: a term t is obstinately rigid iff it designates the same thing in every
possible world, period, whether or not that thing exists in that world.
Rigid designators are contrasted with non-rigid (flaccid) designators.
A good intuitive test for rigidity is to ask yourself whether you can truly substitute the
expression for ‘X’ in the following schema:
(c) The thing that is in fact X might have not been X
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If you can then the expression is flexible. Thus ‘Aristotle’ does not fit truly into (c): the thing
that is in fact Aristotle could not have failed to be Aristotle. On the other hand the thing that
is in fact the last great philosopher of antiquity (i.e. Aristotle) might have not been the last
great philosopher of antiquity—as would have happened if Aristotle had never gone into
philosophy in the first place. All of this has a more familiar temporal analogue: we may
define an expression as temporally rigid if it denotes the same thing at all times of evaluation.
Thus e.g. ‘Aristotle’ is temporally rigid but ‘Miss World’ is not temporally rigid, as can be
seen if we apply a temporal analogue of the intuitive test: ‘The man who was once Aristotle
was once not Aristotle’ is false; but ‘The girl who is now Miss World was once not Miss
World’ is true.
Commitment to rigid designators supports Kripke’s conclusions about the modal status of
identity statements.
Suppose that ‘a’ and ‘b’ are rigid designators and that ‘a = b’ is true.
Since ‘a’ denotes the same object at every possible world as it does at the actual world, it
denotes the same object at every possible world as ‘b’ does at the actual world. But since ‘b’
denotes the same object at every possible world as it does at the actual world, ‘a’ and ‘b’
must therefore be denoting the same object as one another at every possible world. So ‘a = b’
is a necessary truth! Yet discovering that ‘a=b’ is true is a posteriori.
Hence this argument yields examples of necessary a posteriori truth: e.g. it is necessary and a
posteriori that Hesperus = Phosphorus.
--------------------------------------------------------------------------------------------------------DE DICTO & DE RE NECESSITY
(1) The second man on the moon necessarily visited the moon
(3’) Necessarily, the second man on the moon visited the moon
(3*) The second man on the moon is such that, necessarily, he visited the moon
Now, (3’) is analytic, and obviously true. Meanwhile, (3*) is arguably false – after all, the
second man on the moon might have not gone.
The key difference is the scope difference regarding the necessity operator:
(3’) □(x)(…)
(3*) (x)□(…)
The instances where the necessity operator has the wide scope are de dicto necessities; while
those where the necessity operator has narrow scope are de re necessities.
Now, because of the way that rigid designators work, it also turns out that if the designating
term the predicate applies to is rigid, then the necessity will be de re as well.
(Think about whether there is a difference in scope regarding ‘a is necessarily identical to a’)
--------------------------------------------------------------------------------------------------------CAUSAL THEORY OF REFERENCE
A related (but distinct!) question: how proper names come to refer to the things they do.
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The basic idea: there is an initial baptism, involving a kind of pointing, where a referent is
dubbed with the referring term – this is the occasion when the individual involved is first
named.
Following this baptism, the use of this name to refer to the original object spreads throughout
the community of speakers, with the knowledge of what the term refers to being spread
causally.
Note that causation has nothing to do with how the term relates to its reference! All causality
has to do with is how the use of the name spreads, with later uses acquiring the name through
causal contact with earlier users, such that we could, in theory, trace the causal chain all the
way back to the initial baptism.