Thus, the Symmetry Thesis, as weakly construed, is incompatible with

state
230 Chapter 9
types, the weak reading of the Symmetry Thesis maintains that not all
of a subject’s psychological representations can be applicable only to the
first person.
Thus, the Symmetry Thesis, as weakly construed, is incompatible with
the notion that psychological self-awareness is independent of awareness
of other minds, in, for example, the way that seems to be implied by those
versions of the argument from analogy that hold that our capacity to
ascribe psychological properties to others is derived by analogy and extension
from our logically independent capacity to ascribe psychological
properties to ourselves. On most versions of the argument from analogy,
there is no constitutive connection between first-person and thirdperson
ascriptions of psychological properties. The analogy approach to
awareness of other minds generally appears within the context of a debate
predicated on the assumption that it makes perfectly good sense for a
psychologically self-aware subject not to be aware that there are any other
minds at all. Consider the following well-known passage from John Stuart
Mill:
By what evidence do I know, or by what considerations am I led to believe, that
there exist other sentient creatures; that the walking and speaking figures which
I see and hear, have sensations and thoughts, or in other words, possess Minds?
. . . I conclude it from certain things, which my experience of my own states of
feeling proves to me to be marks of it. . . . I am conscious in myself of a series of
facts connected by a uniform sequence, of which the beginning is modifications
of my body, the middle is feelings, and the end is outward demeanour. In the case
of other human beings I have the evidence of my senses for the first and last links
of the series, but not for the intermediate link. . . . Experience, therefore, obliges
me to conclude that there must be an intermediate link. (1889, 243)
The implication here is clearly that apprehending the connections between
the three links in the sequence is independent of the identifying the
presence of two of those links in other subjects and could take place in
its absence. Even on its weak construal, the Symmetry Thesis rules this
possibility out.
A second and stronger reading of the Symmetry Thesis would be that
no subject can discriminate in himself psychological-state types that he
cannot discriminate in other subjects. This is stronger than the first implication,
which leaves open the possibility that, despite the impossibility
of a psychologically self-aware subject being completely unaware of the
existence of other minds, that subject’s understanding of other minds
Psychological Self-Awareness: Self and Others 231
might be impoverished relative to his psychological self-understanding.
This point can be put in a way that matches the previous point: to the
extent that psychological awareness is a matter of ascribing psychological
predicates, whether to oneself or to others, there can be no psychological
predicates which have only a first-person application. Alternatively,
and more broadly, whatever psychological representations a subject has,
none of those psychological representations can have only a first-person
application.
It is important to note, however, that the Symmetry Thesis does not
have any implications for the obvious fact that our ways of finding out
about our own psychological properties can differ fundamentally from
our ways of finding out about the psychological properties of other
people. Typically, we find out about many of our psychological properties
without any need to observe our behavior, whereas observation of behavior
is often required to find out about other people’s psychological
properties. No theory that denied this obvious fact could be true. The
Symmetry Thesis, though, says no more than that the set of capacities
that we put to work in finding out whether or not we instantiate any of
a given set of psychological properties cannot exist in the absence of a
comparable set of capacities to determine whether other people instantiate
any of that same set of psychological properties. It does not require
that it be the same capacities performing both tasks, or that those capacities
be structurally similar in any way.
Let me turn now to the question of why one might think that the Symmetry
Thesis is true. I have already suggested one prima facie piece of
evidence, which is the constancy of sense of psychological predicates
across first-person, second-person and third-person applications. But this
is no more than prima facie evidence. The fact that where a psychological
predicate can be applied in first-, second-, and third-person ways, it means
the same in each application does not entail either that if a subject has
some psychological predicates, he must have at least some with a thirdperson
application (the weak reading) or that none of those psychological
predicates can have only a first-person application (the strong reading).
To move beyond prima facie evidence, the first argument in support of
the Symmetry Thesis that I want to consider draws on a widely accepted
claim about the nature of concept mastery. Although the argument’s most
232 Chapter 9
articulate development has come from Gareth Evans, its origins seem to
lie in some terse remarks of Strawson’s. Here is how Strawson puts the
conclusion of the argument: “It is a necessary condition of one’s ascribing
states of consciousness, experiences, to oneself in the way one does, that
one should also ascribe them, or be prepared to ascribe them, to others
who are not oneself” (Strawson 1959, 99). This seems close to what I
have termed the strong reading of the Symmetry Thesis, namely that no
subject can discriminate in himself psychological-state types that he cannot
discriminate in others. Note, however, that this argument, if sound
(which I shall argue that it is not), would prove the Symmetry Thesis in a
manner that might well turn out to be too restricted. Because it rests crucially
upon a particular view of the requirements for concept mastery,
it is restricted to the discrimination of psychological-state types at the
conceptual level, unless it can be shown that the requirements in question
are not exclusive to conceptual representation.
This following sentence from Strawson conveys the essentials of Strawson’s
and Evans’s position: “The main point here is a purely logical one:
the idea of a predicate is correlative with that of a range of distinguishable
individuals of which the predicate can be significantly, though not necessarily
truly affirmed” (Strawson 1959, 99, n. 1). From this requirement
on predicates in general it follows that psychological predicates must have
a range of distinguishable individuals to which they can be applied. And
this seems to lead to the conclusion that no psychological predicate can
have only a first-person application. Evans has developed the same point
into what he terms the Generality Constraint:
What we have from Strawson’s observation is that any thought which we can
interpret as having the content that a is F involves the exercise of an ability—
knowledge of what it is for something to be F—which can be exercised in indefinitely
many distinct thoughts, and would be exercised in, for instance, the thought
that b is F. And this of course implies the existence of a corresponding kind of
ability, the ability to think of a particular object. (Evans 1982, 103)
We thus see the thought that a is F lying at the intersection of two series of
thoughts: on the one hand, the series of thoughts that a is F, that b is F, that c is
F, . . . and, on the other hand, the series of thoughts that a is F, that a is G, that a
is H. (Evans 1982, 104, n. 1)
Evans’s Generality Constraint imposes a stronger requirement than the
comments from Strawson that gave rise to it. Evans imposes a require-