About Me



KISS Linux

Essentialism and Possibility: Can We Save the Worlds?

In 'A Philosopher's Paradise', Lewis sketches for us a multiplicity of worlds,
all of which are existing possibilities, or ways in which the world could have
been. These worlds are the objects of our modal language, and are what we are
talking about when we discuss possibilities of our world - things that aren't,
but could be potentially, or things that could have been but didn't happen. I
will seek to argue that the essentialist is committed to the thesis that there
are no such possible worlds besides the actual one and thus, considerations of
possible worlds and 'ways things could have been' as existing possibilities are
false. There are, in effect, no other worlds for the essentialist. However, this
claim is not necessarily true for all essentialists. Instead, it is only true in
its strongest sense for the super essentialist. Less maximal essentialists can
appeal to other aspects of Lewis' characterization of possible worlds to keep
their modal language meaningful. I also consider that this does not necessarily
limit the super essentialist's use of modal language. Instead, the essentialist
can consider these possible worlds as being of an abstract kind, not of an
existing kind as Lewis asserts.

The first thing we must consider is the kind of essentialism I'm talking about.
Essentialism is, most broadly, the idea that objects must have some particular
properties. That is to say, that these properties are necessary for these
objects. This is to be contrasted with what has been termed accidental
properties, those properties which are mere accidents of an object, not
necessary for its existence but nevertheless true of it. This account of
essentialism has been argued against [1], but this is something that one would
be inclined to agree with, at least intuitively. For it does seem to be the case
that Socrates is essentially human, and that if Socrates were not human he would
not _be_ Socrates. How far and deep these essential properties of objects might
be I'm not quite sure, but what is important here is that the essentialist
believes that it must be the case that at least some properties of an object are
essential to it [2].  What I have described might be termed some kind of minimal
essentialism, as it isn't the case for people who accept this position to accept
that all properties of an object are essential to it, thus leaving room for some
kind of accidental properties an object could have.  This is to be contrasted
with the super essentialist. The super essentialist believes that all properties
of an object are essential to it. Thus, it is necessarily the case that Socrates
has all of the properties which Socrates has, otherwise he would not be
Socrates. Indeed, Socrates would not exist; he might be someone else, in some
other time or place, or he might not exist entirely.  What matters here is that
this other Socrates, lacking some kind of property, would not be the person we
all come to know and refer to as Socrates. So, given this understanding of
necessary and accidental properties, one might be inclined to ask what this
means for modal language. If all of an object's properties are essential (and
thus necessary), how can we possibly talk of possibility, of ways things could
have been otherwise?

David Lewis begins his discussion in 'A Philosopher's Paradise' with a detailed
picture of the world.  His declaration that "the way things are, at its most
inclusive, means the way this entire world is" (1) is rivalled by the claim that
"things might have been different" (1). In so arguing, Lewis gives to us his
position on possibility and necessity: there is a "plurality of worlds" (2), a
thesis he calls modal realism. These worlds exist in much the way that our own
world does, and there are "countless other worlds" (2), all differing in some
respect to our own, and to each other. These worlds realize the possibilities of
the ways in which our world could have been. Lewis ties this notion of the
nature of possible worlds to modality. He says that "other worlds are
unactualised possibilities... whenever such-and-such might be the case, there is
some world where such-and-such is the case" (5).  We can formalize this
discussion of Lewis' possible worlds semantics for modal logic as follows: 

It is necessary that P is true at a world W iff, for all possible worlds W, P is
true at W.  # It is possible that P is true at a world W iff, for some possible
world W, P is true at W.

Thus the notion of possibility and necessity are born: some particular statement
is necessary only if it holds in all worlds, and it is possible only if it holds
in at least one world. Given this notion of possibility and necessity, one might
wonder if it is indeed the case that the essentialist could possibly talk in
such a way. Put another way: can the essentialist use modal language in this way
and have it still be meaningful? 

The essentialist as we said talks about essential properties in terms of
necessity. This I think, while contentious, can be put aside for now. What might
be more concerning is whether or not the essentialist is able to speak of
'possibility'. Can the essentialist appeal to possible worlds to ask how things
might have otherwise been? It seems to be the case that they cannot. Take for
example, my writing this paper. Perhaps it is essential to me, as a philosopher
or a student, that I write papers, and that I choose topics that might bore my
friends. Could it be the case that in some possible world W that this is not the
case? Given the essentialness of this property, it seems that to say that I
myself as I actually exist could write interesting papers doesn't talk about me
at all. If it is essential that I write in some kind of way about some kind of
thing, and if it were not the case that I do so, then I must be talking about
some other person, a someone who is not me as I am. This person is some other
individual, much like Socrates would not be Socrates if he were not human, did
not die to Hemlock, or was not an Ancient Greek philosopher - they differ in
some meaningful way, a way that defines the person as they are. These people do
not seem to be the people they are purported to be. Thus, it does not seem to be
the case that the essentialist can speak of possible ways the world could have
been. That is to say, the essentialist's body of worlds can only be one, that of
the actual world. Perhaps the essentialist is not bothered by this conclusion.
But at the very least, it seems plausible that the essentialist would like to
talk about possibilities in a more concrete, meaningful way. Is there a way for
the essentialist to save the worlds? I think that this question breaks apart
into cases: one for the more minimal essentialist [3] , and one for the super

It seems that the essentialist does have a way of speaking about possibilities
meaningfully. Indeed, this possibility is sketched out by Lewis. He considers
what it would be for a person to have counterparts across worlds and how such an
analysis might impact modal language. A counterpart of x is all of the y's
across possible worlds which resemble x over a portion of their history in each
of their respective worlds.  This resemblance relation can be spoken of as being
a sharing of some essential properties, perhaps. Thus, when the essentialist in
our actual world speaks of possibilities, what they are actually speaking of is
ways in which their class of counterparts could be in their own world. She is
constructing a map between herself and her counterpart in the relevant way to
speak of how she would have been or might have come to be. This might seem to be
a vague way of talking about counterparts (what exactly might this resemblance
the essentialist is seeing be, after all), but that is due to the sheer
abundance of properties. In order to satisfy the inquirer as to what
counterparts it is that they are resembling, they need only outline the
particular kinds of properties that they are thinking of when they describe how
their counterpart is similar (and different). Thus, the essentialist can speak
of possibilities under Lewis' framework of modal realism.

But what of the super essentialist? It looks as though she is far more strongly
committed to the actual world as being the only world. If every property of x is
essential to x, it seems to be the case that every counterpart x would have in
any possible world W would exactly resemble that x. Since x exists only in the
actual world, it must be the case that all of x's counterparts exist in the
actual world.  That is to say, x herself is (perhaps trivially) her only
counterpart. The super essentialist could perhaps commit herself to never
speaking of possible ways the world could be, but this seems unsatisfactory and
contrary to the ways we ordinarily speak. So perhaps instead, the super
essentialist could suspend her belief in the brief moments in which she speaks
of possibilities. She could, as it were, construct her own world that represents
the possibility she wishes to talk about. When she expounds upon a possibility,
she may be charged with violating her own philosophy. But she can recover! If
she were to outline a set of propositions, growing in depth and detail stemming
from her own position in this possible world, until she had satisfactorily
constructed a world for her interlocutor. Of course, this world would not exist
in any way remotely resembling the way Lewis takes worlds to exist, in a real
and literal sense.  Instead, these worlds would be objects of severe
abstraction, collections of propositions constraining the imagination of those
who hear them. In this proposition world there are no counterparts, there is no
resemblance relation between her and her possible self. There is only a person
who exists in a particular way, and this person is who we are take the super
essentialist to be speaking of when she talks about possible ways the world
could be. It is the case then that possible worlds are not real for the super
essentialist. Instead, they are mere abstracta, objects of thought that we
consider to be real insofar as they allow us to discuss what we mean by a

In this paper I have argued that the essentialist and super essentialist seem
committed to abandoning modal language as they relate to possible ways the world
could be. That is to say, the only world that exist for the essentialist is the
actual world. While there are good reasons to think that this is the case, it
also seems plausible that both the essentialist and the super essentialist could
find ways out of this problem. Indeed, they can appeal to their resemblance to
their counterparts or to abstract worlds constructed from propositions to give
their modal language content that people can understand. While these ways of
thinking about possibilities might not seem to align entirely with our usual way
of speaking about possibility, they aren't necessary ways of talking about
possibility. One is free to do away with these constraints on speaking when it
isn't beneficial for communicating, after all. It is only when one tries to
understand what the essentialist is referring to or what situations they are
talking about that this further elaboration may be necessary. The super
essentialist diverges most sharply from Lewis in this regard, however. Possible
worlds, for the super essentialist, do not exist, and are really only worlds of
an abstract kind; a collection of propositions left to describe only a small and
relevant part of the world as it could have been. 


[1] See Kit Fine's 'Essence and Modality' 
[2] Whether or not this notion of essentialism can be extended to things people 
would not call objects (numbers, concepts, etc.) I don't really consider here 
in this paper 
[3] Further referred to simply as 'the essentialist'


Dilyn Corner (C) 2020-2022