The Oxford Companion to Philosophy Part 95 pdf

time, thus partaking in a tradition stretching back to
Parmenides and Zeno, who held the appearance of
temporal change to be an illusion.
In opposition to the ‘static’ view stands the ‘dynamic’
view of time, traceable back to Aristotle and before him to
Heraclitus. By this account the future lacks the reality of the
past and present, and indeed reality is continually being
added to as time passes. The objection mentioned earlier is
not difficult to overcome, since even the theory of relativity
acknowledges that some events are past and others future,
no matter which frame of reference is selected, and these
may be said to lie in the absolute past or future. The relativ-
ity of simultaneity only requires us to revise our conception
of the present, allowing it to embrace all events not causally
connectable to us by a physical signal. A more serious
challenge to the dynamic view of time comes from an argu-
ment of J. M. E. McTaggart, who claimed that the notion of
temporal becoming (bound up with the *A-series of past,
present, and future) leads to contradiction. But it seems fair
to protest that McTaggart’s argument demonstrates not so
much the absurdity of the notion of temporal becoming as
the incoherence of his representation of that phenomenon.
According to McTaggart, the phenomenon supposedly
consists in future events ‘becoming present’ and then
‘receding into the past’, whence it apparently follows,
absurdly, that all events are past, present, and future. But
the lesson is just that we should not think of ‘the present’ as
somehow ‘moving’ along the sequence of events from past
to future. In denying the reality of the future, we may
appeal to the fact that not all future-tensed statements
appear to be determinately true or false.

The asymmetry of time is perhaps its most striking fea-
ture and the most difficult to explain. The fundamental
laws of physics are time-reversible, and yet complex
macroscopic processes like the growth of a tree or the
breaking of a glass could not happen in reverse save by a
miracle. This is often supposed to be explicable by refer-
ence to the second law of thermodynamics, which implies
that closed systems tend to evolve from conditions of less
to greater disorder, or ‘entropy’. But why should the uni-
verse have been created in a particularly low state of
entropy—or was this just an accident without which time
might have been isotropic? And how does the asymmetry
of time as we know it relate to the apparent non-existence
of phenomena involving *‘backwards’ causation, such as
*time-travel? These are problems which are still very little
understood by either metaphysicians or physicists. e.j.l.
*endurance and perdurance; persistance through time;
presentism; space-time; specious present; tense.
P. Horwich, Asymmetries in Time (Cambridge, Mass., 1987).
J. R. Lucas, The Future (Oxford, 1989).
R. Le Poidevin and M. MacBeath (eds.), The Philosophy of Time
(Oxford, 1993).
time preference. We are often prepared to opt for a good
thing now even if we know that a better thing can be
obtained later with at least as much probability. This sort
of attitude is known by decision theorists as time prefer-
ence, and the question of its rationality is much debated.
Some suggest that time preference is a biologically
evolved strategy to discount future goods—a sensible
enough one for creatures for whom the calculation of

future probabilities would be too difficult or a waste of
cognitive resources. e.j.l.
*decision theory.
R. Nozick, The Nature of Rationality (Princeton, NJ, 1993).
time’s arrow. Time has, it seems, both a ‘forward’ and a
‘backward’ direction, unlike any of the dimensions of
space. But is this a feature internal to *time itself? Is it
related to *causal asymmetry? If an event e is earlier than
another event d, then, unless time is circular, d is not also
earlier than e. But in virtue of what is one event or
moment of time earlier, rather than later, than another?
Some philosophers attribute time’s ‘arrow’ or directional-
ity to the Second Law of Thermodynamics, which says, in
effect, that complex systems become increasingly dis-
ordered over time: glass vases frequently break into frag-
ments, but fragments of glass never reassemble
themselves into intact glass vases. However, the funda-
mental laws of physics appear to be time-symmetric,
which makes the Second Law appear to be a contingent
consequence of the fact that the physical universe came
into existence at the Big Bang in a highly ordered state.
Why, though, should we say that the Big Bang was at the
beginning, as opposed to the end, of time? e.j.l.
S. F. Savitt (ed.), Time’s Arrow Today (Cambridge, 1995).
time-travel. The philosophy of time-travel is a serious
subject with a burgeoning literature. Early objections to
the logical possibility of time-travel have now been
answered. For instance, there is no contradiction is saying
that the time-traveller has gone back 100 years in time but
become a day older in the process, provided we distin-

guish between ‘external’ or ‘historical’ time and the ‘per-
sonal’ time of the traveller. Again, it is no objection to say
that if time-travel were possible the time-traveller could
murder his own grandparents and thus prevent his own
birth: for time-travel is not a licence to change the past, but
at most to affect it—and, given that the time-traveller was
born, no effect he has on the past can alter that.
The philosophical value of imagining cases of time-
travel lies in what such *thought experiments reveal about
our concepts of time, *causality, *personal identity, and
the like. e.j.l.
P. Horwich, Asymmetries in Time (Cambridge, Mass., 1987).
‘to be’, the verb. Russell declared that it was ‘a disgrace to
the human race’ that it used the same word in such differ-
ent contexts as the following: ‘John is bald’, ‘There is a
robin on the lawn’, ‘A dolphin is a mammal’ and ‘The
square of three is nine’. These uses of ‘be’ have been called
respectively the copulative, the existential, the class-inclusion,
and the identity use of ‘be’. Aristotle too had affirmed that
the Greek equivalent of ‘be’ was used in more than
920 time
one way (Metaphysics v. 7), although his list of the different
ways is not the same as Russell’s. Medieval philosophers
were divided on the matter, Aquinas following Aristotle
and maintaining that being was ‘analogical’, i.e. had differ-
ent though connected senses, and others such as Duns
Scotus insisting on the univocity of being, i.e. that ‘be’ had
only one sense. Arguably all these senses can be reduced to
two, the copulative and the existential sense. In its exis-
tential sense ‘be’ seems to be doing work otherwise done

by ‘some’: ‘There are blue buttercups’ means ‘Some butt-
ercups are blue’. In its copulative sense ‘be’ seems to have
the purely syntactic function of converting a non-verbal
expression into the equivalent of a verb: ‘is a smoker’ is an
alternative to ‘smokes’. These two uses seem to have little
to do with each other, and it is tempting to regard the verb
as used in these two ways as purely equivocal, i.e. as hav-
ing two unconnected senses. But this plurality of senses is
a phenomenon which occurs in practically all languages
(see John M. W. Verhaar (ed.), The Verb ‘Be’ and its
Synonyms (Dordrecht, 1967–72)), so it is difficult to regard
it as accidental. For one attempt to explain it, see C. J. F.
Williams, What is Existence? (Oxford, 1981), chapters 1
and 12. c.j.f.w.
*being; existence.
token. Contrasted with ‘type’, originally in semiotics, and
nowadays in the formulation of identity theses in philoso-
phy of mind.
A ‘token’ was said by Peirce to be a ‘replica of a symbol’.
Tokens, then, are particular meaningful items, which
belong to the same type (or replicate the same symbol) if
and only if (very roughly) they have the same significance.
Following Peirce it can be said, for example, that there are
three tokens of the word ‘the’ (that type) in the previous
sentence, and that the actual book you’re now reading is a
token of the type Oxford Companion to Philosophy.
In recent philosophical usage of ‘type’ and ‘token’, dif-
ferent kinds of abstraction from that which concerned
Peirce are thought to relate tokens (particulars) to types
(abstract things). It is said, for instance, that the event

which is your now reading is a token of the type reading,
and that the event which is Jane’s believing that p is a token
of the type belief that p. j.horn.
Colin McGinn, ‘Anomalous Monism and Kripke’s Cartesian Intu-
itions’, Analysis (1977).
C. S. Peirce, ‘On the Algebra of Logic’, in Collected Works of Charles
Sanders Peirce, ed. C. Hartshorne and P. Weiss (Cambridge,
Mass., 1931–5), iii.
Toland, John (1670–1722). A radical thinker, born a
Roman Catholic in the north of Ireland, who, after aban-
doning Catholicism at 15—by ‘his own reason and such as
made use of theirs’—moved from latitudinarianism, to
*deism, and finally to a materialistic form of *pantheism,
coining the word ‘pantheist’ in 1705. Toland’s deism is
most evident in his Christianity not Mysterious (1696), a
seminal work in both free thought and Irish philosophy.
His pantheism is developed esoterically in Letters to Serena
(1704)—which contains an acute attack on Spinoza’s the-
ory of matter—and more openly in Pantheisticon (1720).
He was a prolific controversialist and scholar. His Tetrady-
mus (1720) contains the first published essay on the eso-
teric–exoteric distinction, a distinction important for
understanding his own views as well as those of his fellow
free thinkers, such as Anthony Collins. d.ber.
R. E. Sullivan, John Toland and the Deist Controversy (Cambridge,
Mass., 1982).
tolerance, principle of: see Carnap.
toleration. Requires people to coexist peacefully with
others who have fundamentally different beliefs or values.
Within Western political philosophy, toleration was first

discussed during the Wars of Religion between Catholics
and Protestants. When the attempt to impose a single reli-
gion failed, the assumption that political stability required
a common religion was replaced by the principle of toler-
ation. This principle has now been extended to other areas
of moral disagreement, including sexual orientation and
political belief. Why should we tolerate those whom we
see as mistaken, or as heretics? Arguments for toleration
include the fallibility of our beliefs, the impossibility of
coercing genuine religious belief, respect for autonomy,
the danger of civil strife, and the value of diversity. These
parallel the arguments for liberalism. Theorists of toler-
ation include Spinoza, Locke, Voltaire, and Mill; critics
include Rousseau and Comte. w.k.
Susan Mendus, Toleration and the Limits of Liberalism (New York,
1989).
tone. Used by philosophers to translate Frege’s Beleuch-
tung and Farbung. Followers of Frege and J. L. Austin dis-
tinguish three ways in which a word or construction can
have *meaning: by determining what the speaker says; by
indicating whether the utterance is a statement, order,
promise, or what not; and (thanks, perhaps, to its sound or
associations) by making the utterance more or less apt to
affect the state of mind of someone who understands what
is said—to illuminate or confuse, to arouse or quiet a feel-
ing. This last is its contribution to tone. w.c.
W. Charlton, ‘Beyond the Literal Meaning’, British Journal of Aes-
thetics (1985).
M. Dummett, Frege: Philosophy of Language (London, 1973),
ch. 5.

topic-neutral. The term was introduced by Ryle for
expressions that indicate nothing about the subject-
matter, for example, ‘inside’ indicates place, and so is not
topic-neutral, but ‘of ’ is topic-neutral. Smart introduced a
much more specific sense in which a topic-neutral analysis
of a property term entails neither that the property is phys-
ical nor that it is non-physical. He gave topic-neutral
analyses of mental terms which were the first functionalist
identity-claims. Further, he argued that anyone who
accepts an empirical physicalist or functionalist identity
topic-neutral 921
thesis (e.g. pain = c-fibre stimulation, or pain = such-and-
such a computational state) should also accept a topic-
neutral (functionalist) conceptual analysis of mental-state
terms. Suppose S
17
is a brain state or a functional state and
that the claim that pain = S
17
is offered as an empirical
identity-claim. Then the terms flanking the ‘=’ must pick
out the common referent via different modes of presenta-
tion. The mode of presentation of ‘pain’, however, pre-
sumably will be something mental, even something
phenomenal, requiring the empirical identity theorist to
claim that the mode of presentation is also a physical–
functional state, say, S
18
. A regress can be avoided only by
accepting an a priori identity, and the only candidate is a

topic-neutral analysis of mental-state terms in terms of the
states’ normal causes and effects. (Only in an a priori iden-
tity will the terms flanking the ‘=’ refer via the same mode
of presentation.) Thus, according to Smart’s argument,
empirical identity-claims engender topic-neutral analyses.
n.b.
*identity theory; functionalism.
Stephen White, ‘Curse of the Qualia’, Synthese (1986).
tradition. Customary sets of belief, or ways of behaving of
uncertain origin, which are accepted by those belonging
to the tradition as persuasive or even authoritative
and which are transmitted by unreflective example and
imitation.
It is a conceptual joke for a school to announce that as
from June it will be a tradition that . . . The nature of trad-
itions is such that they cannot (logically) be willed; rather
they have grown up. Traditions exist in all areas of life—
literature, religion, legal institutions, and so on—but the
term is of particular interest in political philosophy. For
those political philosophers hostile to the idea of tradition
it is perceived as representing entrenched privileges hold-
ing back political and social progress, and it is to be con-
trasted with a vision of human beings controlling their
own destinies with rational decisions and asserting ratio-
nally based rights. This latter was the position of revolu-
tionary political thinkers such as Rousseau, Tom Paine,
and Richard Price. Their position was opposed by thinkers
such as Edmund Burke, who had less faith in reason. For
traditionalists like Burke social life is kept going not
mainly by rational decision-making but by feeling, habit,

emotional attachments, and conventions. r.s.d.
*conservatism; revolution; reform.
Charles Parkin, The Moral Basis of Burke’s Thought (Cambridge,
1956).
tragedy. Philosophical reflection on tragic drama is as old
as tragedy itself. Plato found tragedy antithetical to philoso-
phy, claiming that it nourishes an irrational part of the soul
which takes pleasure in empathizing with fierce emotions.
Indeed, only by opposing tragedy’s pre-eminence, and its
claim to provide a comprehensive ethical education,
could Plato establish philosophy’s claim to be uniquely
concerned with truth and the good. Aristotle, in response,
saw tragedy as a representation of universal truths which
engages our pity and fear in a beneficial way. Of later
views, Nietzsche’s is the most well known. For him,
tragedy unites a terrifying insight into the destructibility of
the individual (associated with Dionysus) with the beauti-
ful dream-image (associated with Apollo), producing a
uniquely powerful form of art. Tragedy continues to fasci-
nate philosophers interested in aesthetics and moral psy-
chology. c.j.
Aristotle, Poetics.
transcendence. Existence beyond; independent exist-
ence. For example, God, numbers, and universals are
sometimes held to exist beyond space, time, the physical
world, or experience (in some non-spatial sense of
‘beyond’). In theology, the transcendence of God is con-
trasted with his immanence or pervasion of the world. In
medieval philosophy, the transcendentals are notions that
are too fundamental to be accommodated in Aristotle’s

ten categories: for example, unity, truth, goodness, and
being. In Kant’s critical philosophy, ‘transcendent’ know-
ledge of non-spatio-temporal reality that cannot be
subsumed under the *categories is impossible; ‘transcen-
dental’ knowledge, *a priori knowledge of how know-
ledge is possible, is possible and is the content of the
critical philosophy.
One of the most fundamental and persistent divisions
within philosophy is between philosophers who think
there is a transcendental reality and those who do not.
Indeed, the history of philosophy can be understood as the
recurrent advocacy and repudiation of transcendence. A
clue to understanding belief in metaphysical reality lies in
taking the world with which we are acquainted as only
part of a greater whole. The known arguably depends
upon the unknown, because metaphysical questions can
be raised within and about the empirical world but cannot
be answered by any further empirical inspection: Why is
there a universe? Why is a particular person oneself? Why
is it now, now? What is being? Is there life after death?
s.p.
Aquinas, Selected Philosophical Writings, tr. Timothy McDermott
(Oxford, 1993), 51ff.
Immanuel Kant’s Critique of Pure Reason, tr. Norman Kemp Smith
(London, 1978).
transcendental analytic. This is Kant’s title for the
portion of the Critique of Pure Reason dealing with the
nature and function of the understanding. Kant argues
that the understanding is equipped with a set of *a priori
concepts or *categories, including substance and causal-

ity, which are required for the knowledge of an object or
an objective realm. From this he concludes that all objects
of possible experience must conform to these categories.
h.e.a.
H. J. Paton, Kant’s Metaphysic of Experience (New York, 1936).
transcendental arguments. Anti-sceptical arguments
of the form: There is experience; the truth of some
922 topic-neutral
proposition p is a conceptually necessary condition of the
possibility of experience; therefore p. Kant, with whom
transcendental arguments are mainly associated,
regarded them as only capable of providing *synthetic a
priori knowledge of the world as it appears rather than as
it is in itself. q.c.
I. Kant, ‘The Discipline of Pure Reason in Regard to its Proofs’, in
Critique of Pure Reason, tr. N. Kemp Smith (London, 1929).
R. Stern (ed.), Transcendental Arguments: Problems and Prospects
(Oxford, 1999).
transcendental deduction. Kant’s name in the Critique of
Pure Reason for the reasoning which simultaneously justi-
fies both the applicability of the pure concepts of the
understanding (*categories) to objects of experience and
the objectivity of experience itself. The term ‘deduction’
here is borrowed from contemporary jurisprudence
regarding the need to address matters of right as well as of
fact. Starting from the fact that all my representations are
grasped together in one consciousness (the unity of apper-
ception), the argument asserts that such unity is possible
only because synthesized according to the rules contained
in the pure concepts. a.h.

H. E. Allison, Kant’s Transcendental Idealism: An Interpretation and
Defense (New Haven, Conn., 1983), ch. 7.
transcendental idealism is Kant’s name for his overarch-
ing metaphysical doctrine. Some commentators confine
the name to Kant’s own version of the doctrine, while
some extend it to other self-proclaimed versions, notably
Schopenhauer’s, and even to positions, like S
´
an
.
kara’s, that
anticipated Kant’s. Transcendental idealism maintains,
in Kant’s version, that the world as known to creatures
like ourselves, who rely on perceptual experience and
conceptual understanding, is not the world of *things-in-
themselves—of things as they are independently of cogni-
tion— but of ‘appearances’. We have knowledge only of
*phenomena (things in the sensible realm), and not of the
*noumena which are knowable only by a being, like God,
capable of a non-sensory ‘intellectual intuition’. For
example, we experience the world as spatio-temporal,
even though space and time are ‘forms of (our) sensibil-
ity’, not features of reality-in-itself. Kant favourably con-
trasts his transcendental idealism with transcendental
realism and empirical idealism, which respectively hold
that our knowledge extends to things-in-themselves, and
that objects of experience are not grounded in extra-men-
tal reality. Schopenhauer criticized Kant for overlooking a
non-representational mode of knowledge whereby we
are acquainted, albeit imperfectly, with reality-in-itself as

*will. d.e.c.
H. E. Allison, Kant’s Transcendental Idealism: An Interpretation and
Defense (New Haven, Conn., 1983).
A. C. Ewing, Idealism: A Critical Survey, 3rd edn. (London, 1974).
transcendentalism. The word ‘transcendentalism’ can be
applied either to something large, shapeless, and generic
or, more straightforwardly, to something historically and
geographically distinctive, which willingly accepted the
name. In the larger sense transcendentalism is belief in the
existence of things that transcend sense-experience or,
more reflectively, belief in the possibility of transcendent
metaphysics, that is to say, philosophical reasoning which
aims to establish beliefs about transcendent entities. *God
might seem an obvious example of a transcendent, but
those who accept religious or mystical experience as a
source of knowledge might resist that. The *Forms or
Ideas of Plato, which are not in space and time and not
encountered in the world of the senses, are more incon-
testably transcendent. Some have said, or, like Berkeley,
implied, that Locke and representationalists generally,
who take our beliefs in the existence of material things to
be causal inferences from our sense-experiences, are tran-
scendent metaphysicians. Many philosophers of science,
along similar lines, have said the same about belief in the
literal existence of such theoretical entities as atoms and
subatomic particles.
Transcendent metaphysics has been attacked in two
main ways. In the first place it can be argued that there can
be no rational warrant for the inferences that transcenden-
tal metaphysicians make from experience to what tran-

scends it. Secondly, it has been argued by positivists of
various kinds that since the terms that figure in the utter-
ances of transcendent metaphysicians have no criteria of
empirical application, those utterances are devoid of mean-
ing. The philosophy of Kant contains elements of both
approaches. He does not deny meaning to the theses that
the world is infinite in size or has a first cause (and their
opposites), but he holds them to be undecidable or
unknowable for the reason that the concepts employed in
them are being used outside the sphere of their legitimate
application, which is within experience. To make things
more complicated he also holds that there are transcendent
things-in-themselves, noumenal objects or selves, indeed,
perhaps, that these are the only truly real things that there
are. With a final turn of the screw he describes his own
inquiries and their results as transcendental, meaning by
this not that they are concerned with the transcendent, but
that they are concerned with the possibility of knowledge.
More definite in outline, if not in content, is *New Eng-
land Transcendentalism. This was the body of ideas elab-
orated by Emerson and a group of associates—among
them Thoreau, George Riley, Orestes Brownson, and
Bronson Alcott—who lived in or met at Concord, Massa-
chusetts between about 1830 and 1860. It was a very
diluted variety of philosophical thought. Plato and Plot-
inus, Coleridge and Carlyle, Eastern scriptures, German
mystics like Boehme and the Romantic German idealists,
all contributed to a doctrine which stressed the spiritual
unity of the world (thus interpreting God in an untran-
scendentally pantheistic way) and the superiority of intu-

ition as a source of knowledge as opposed to logical
reasoning and sense-experience. They relied heavily on
the distinction of true reason from the merely analytic
understanding, the doctrinal cornerstone of *philosoph-
ical Romanticism. It supplied a foundation for the
transcendentalism 923
‘spiritual religion’ they upheld against the natural religion of
the Enlightenment and the revealed religion of Calvinism.
As important deliverances of intuition they affirmed
the natural goodness of man and his freedom, in oppos-
ition to the emphasis of *Calvinism on original sin and pre-
destination. Many of the Transcendentalists had started
out as Unitarians. Rejecting the Calvinist orthodoxy of
their time and place, they were equally hostile to scientific
materialism, the conception of the world formed by the
mere understanding.
New England Transcendentalism was more a social
movement than a philosophical school. It expressed itself
in the formation of ideal communities such as Brook
Farm—the inspiration of Hawthorne’s Blithedale Romance.
Its adherents took progressive positions on the emancipa-
tion of women and the abolition of slavery. a.q.
O. B. Frothingham, Transcendentalism in New England (New York,
1876).
Perry Miller (ed.), The Transcendentalists (Cambridge, Mass.,
1950).
P. F. Strawson, The Bounds of Sense (London, 1966).
W. H. Walsh, Metaphysics (London, 1963), ch. 3.
transcendental unity of apperception: see apperception.
transitive relation. A binary, i.e. two-term, *relation is

transitive when if anything x has it to anything y, and y to
anything z, then x has it to z (in symbols, R is transitive
if and only if
∀x∀y∀z((Rxy Ryz) → Rxz)); for example,
being older than. ‘Intransitive’ means: if anything x has it to
anything y, and y to anything z, then x does not have it to
z; for example, being twice as old as. ‘Non-transitive’ may
mean either ‘not transitive’ or ‘neither transitive nor
intransitive’. c.a.k.
W. Hodges, Logic (Harmondsworth, 1977).
translation, indeterminacy of. W. V. Quine argued that
there are no uniquely correct translations between lan-
guages. This is not the banal point that languages contain
words with no precise equivalents in others, but the extra-
ordinary claim that there is no such thing, ever, as a uniquely
correct translation of a word. It forms part of Quine’s argu-
ment that ‘there is no objective matter to be right or
wrong about’ where the *meaning of words is concerned
(Word and Object, 73), and it has implications in the philoso-
phy of mind: if words have no meaning, then beliefs and
other *propositional attitudes do not exist. Quine sees this
as an acceptable result of behaviourist psychology; the
apparatus of stimulus and response will not vindicate
common-sense views about meaning, and ‘the very ques-
tion of conditions for identity of propositions presents not
so much an unsolved problem as a mistaken ideal’ (Word
and Object, 206).
The doctrine arises from Quine’s dissatisfaction with
the Logical Positivists’ version of the distinction between
*analytic and synthetic statements, which requires the

meanings of words to be explained in terms of the experi-
ences appropriate or inappropriate to their use. Quine
retorts that single words cannot be paired with experi-
ences, since they confront experience in clusters. His cele-
brated illustration involves an imaginary community who
say ‘gavagai’ when confronted by a rabbit. Other things
being equal, it is natural to translate the word as ‘rabbit’.
But why not translate it as, say, ‘undetached rabbit-part’?
For any experience which makes the use of ‘rabbit’ appro-
priate would also make that of ‘undetached rabbit-part’
appropriate.
One reply is that we should discover what their word
for ‘same’ is (let us say ‘emas’) and then point to different
parts of a rabbit and see if the community’s members
keep agreeing that this is the ‘emas gavagai’. One would
expect them to dissent at some point if this phrase trans-
lates ‘same undetached rabbit-part’. However, how are
we to obtain the translation of ‘emas’? It seems that this
awaits translation of words like ‘gavagai’. For if this trans-
lates as ‘rabbit’, then their failure to dissent from ‘emas
gavagai’ indicates that the latter may translate as ‘same
rabbit’. But if ‘gavagai’ translates as ‘undetached rabbit-
part’, then their failure to dissent indicates that ‘emas gav-
agai’ should translate as, say, ‘part of the same group of
undetached rabbit-parts’. We are trapped in a circle, and
Quine contends that this always happens if we try to trans-
late ‘gavagai’ by translating other words first. Since
experience is not enough to tie down individual words,
there is no initial point on which to base a uniquely correct
translation.

A different reply is that finding out more about the
brains and nervous systems of the members of the com-
munity would indicate which translation is correct. But
Quine argues that the indeterminacy thesis holds even
given all facts about the world (past, present, and future)
that could be stated in terms of physics. The situation here
is delicate: on the one hand, Quine’s critics accuse him of
unfairly restricting the range of facts relevant to transla-
tion, while he on the other replies that such critics beg the
question by smuggling in assumptions about meaning and
translation.
The imaginary community is only a metaphor. If there
is nothing to choose between linguist A’s translation of
‘gavagai’ as ‘rabbit’, and linguist B’s translation of it as
‘undetached rabbit-part’, then why should not B translate
A’s uses of ‘rabbit’ as ‘undetached rabbit-part’? Hence, if
the argument works, it works within a single language.
Responses tend to involve attacks on Quine’s *behav-
iourism. But this is not the best approach to his nihilism
about meaning, given the currency of nihilism in philoso-
phy of mind (and critical theory). The root of the trouble
lies in attempts to give ‘scientific’ accounts of language
and thought, and Quine’s outlook is more typical of its
time than some treatments indicate. g.w.m
cc.
C. Hookway, Quine (Cambridge, 1988), pt. iii.
R. Kirk, Translation Determined (Oxford, 1986).
W. V. Quine, Word and Object (Cambridge, Mass., 1960),
ch. 2.
transparency: see opacity and transparency.

∨
924 transcendentalism
transposition (also known as *contraposition). The rule
in classical logic whereby we derive ‘If not-q then not-p’
from ‘If p then q’. While admitting its occasional accept-
ability, many find transposition (‘an antiquated notion’:
Dudman) deeply suspect. Difficult cases include ‘There’s
cake if you want it’, and Prior’s ‘If God exists, go to
church’. Transposition is the sentential-logic analogue of
the argument form *modus tollens, and of traditional logic’s
contraposition (whereby from a given sentence we infer
another whose subject is the contradictory of the ori-
ginal’s predicate). j.j.m.
V. H. Dudman, ‘Parsing “If”-Sentences’, Analysis (1984).
transvaluation of values (or revaluation of values).
Nietzsche’s project of reassessing the worth of things
commonly valued positively or negatively. He proposed
and undertook to revalue them in terms of their ‘value for
life’, i.e. the extent to which they are conducive or detri-
mental to the preservation and enhancement of various
types of human beings and of human life more generally.
This is neither to devalue nor to reverse all prevailing
*value-determinations, but rather to revise them in a nat-
uralistic manner sensitive to the varying requirements of
human flourishing. (See e.g. Beyond Good and Evil, sect. 4;
Genealogy of Morals, preface; The Antichrist, sects. 1–7.)
r.s.
George Morgan, What Nietzsche Means (New York, 1965), ch. 5.
traversal of the infinite. An argument for the finitude of
the world’s past which originated with Philoponus

(490?–575?). An infinite series cannot be completed (the
infinite cannot be traversed). But if the world were infinite
in past time, then ‘up to every given moment an eternity
has elapsed’ (Kant) and thus an infinite sequence would
have been completed. Therefore the world is finite in past
time. This argument has been offered by, among others,
al-Ghaza¯lı¯, St Bonaventure, and Kant. It was, however,
decisively refuted by Aquinas and, somewhat more sub-
tly, by Ockham. Aquinas pointed out that traversal
requires two termini: a beginning and an end. But any past
time which could count as a beginning is only a finite time
ago. Consequently we do not, in the required sense, have
a traversed infinity. j.j.m.
*infinity.
Norman Kretzmann, ‘Ockham and the Creation of the Begin-
ningless World’, Franciscan Studies (1985).
triangulation. Davidson invokes this puzzling notion
while arguing that thought is an essentially social phe-
nomenon. The content of our thoughts, he contends, is
determined by their causes. Yet, when you see, and think,
there is a table before you, many causal factors contribute
to your having this thought. What makes it a thought
about the table as opposed to some other link in the causal
chain (e.g. your retinal image)? Davidson maintains that
this question cannot be answered if we consider you in isol-
ation. Once we introduce another person, it becomes evi-
dent that communication is possible only on the assump-
tion that your respective thoughts converge on public
objects of a shared world. The ‘triangle’ <person-person-
object> is essential to the determination of the mental

content and thus, as Davidson puts it, there can be no first
person without a second person. d.bak.
Donald Davidson, Subjective, Intersubjective, Objective (Oxford,
2001).
trolley problem. Suppose you are driving a trolley whose
brakes have failed. Ahead of you five people are standing
on the track. But here the track forks, and on the alterna-
tive path one person stands. Is it morally permissible, or
even required, to divert the trolley to save the five from
death, at the cost of one? Most people’s intuition is that
this is at least morally permissible. Why, then, do we not
think it permissible for a surgeon, in urgent need of five
different organs to save five patients, to kill a healthy
patient to procure them? s.d.r.
*acts and omissions.
Philippa Foot, ‘The Problem of Abortion and the Doctrine of Dou-
ble Effect’, reprinted in her Virtues and Vices (Oxford, 1978, 2002).
Judith Jarvis Thomson, ‘The Trolley Problem’, reprinted in her
Rights, Restitution and Risk (Cambridge, Mass., 1986).
trope. The term ‘trope’ was introduced into philosophy
by D. C. Williams to mean a particular unrepeatable prop-
erty, like the particular blueness of a blue patch that can-
not be shared by any other patch, not even a patch that
exactly matches the blue patch in colour. Other patches
may nevertheless share the same shade of blue by virtue of
the fact that their particular bluenesses resemble one
another. Tropes are to be contrasted with *universals,
which are repeatable properties, like a specific shade of
blue that can be shared by many different patches. A par-
ticular property may be thought to be a complex of a par-

ticular (a patch) and a universal (a shade of blue). By
contrast, trope theory claims, a trope is not complex but
simple. f.m
acb.
*properties, individual; universals.
Donald C. Williams, ‘On the Elements of Being: I’, in D. H. Mel-
lor and A. D. Oliver (eds.), Properties (Oxford, 1997).
Trotsky, Leon (1879–1940), real name Lev Davidovich
Bronstein. The most famous of the Bolshevik leaders after
Lenin, Trotsky played a prominent role in the 1917 Revo-
lution and its aftermath, only to be subsequently exiled
and murdered by Stalin. Although less interested in phil-
osophy than most of his fellow Bolsheviks, Trotsky did
address himself to these matters on two occasions. First in
the 1920s he became interested in the philosophy of sci-
ence. He defended the heterogeneity of the sciences,
argued against those who assimilated the method of social
science to that of natural science, and refused to claim that
dialectical materialism was integral to the creativeness
of science. Trotsky displayed the same approach in
psychology through his continued preference for the
Trotsky, Leon 925
imagination and enterprise of Freud over the plodding
behaviouralism of Pavlov.
Towards the very end of his life, however, Trotsky
dealt more systematically with philosophical questions—
but with regrettable results. Prompted by the attack on
Marxist philosophy by his hitherto loyal lieutenants Burn-
ham and Shachtman, Trotsky wrote In Defence of Marxism
which consisted in a dogmatic insistence on the essential-

ity of *dialectical materialism to Marxism. For Trotsky
here, the politics and economics of Marxism had to be
ensconced within the framework of a consistent and well-
defined philosophical outlook. Anyone who divorced
sociology from dialectical materialism and politics from
sociology would, in the end, lose any capacity for political
activity. d.m
cl.
B. Knei-Paz, The Social and Political Thought of Leon Trotsky
(Oxford, 1978).
true for me: see relativism, epistemological.
trust. Whether one trusts a specific other commonly
depends on whether one thinks the other is trustworthy in
the relevant circumstances. This depends on what know-
ledge one has of the other’s future commitments to behave
as one trusts. Some writers treat trust as a matter of
rational assessment and rational choice on the parts of both
the truster and the trusted. Perhaps because of its relation
to trustworthiness, some theorists treat trust as inherently
normative—even to the point of assigning an obligation of
trustworthiness to one who is trusted. John Locke thought
trust central to consensual government. Contrary to the
purely rational-choice vision, many theorists suppose that
only a normative commitment to some degree of trust-
worthiness can explain the success of many institutions
and organizations in serving their clienteles. r.har.
*consent; testimony; loyalty.
Diego Gambetta, Trust: Making and Breaking Cooperative Relations
(New York, 1988).
truth. The term ‘truth’ seems to denote a property, one

which is also expressed by the truth-predicate ‘is true’. But
if so, of what is truth a property? What are the primary
‘bearers’ of truth, and of its counterpart, falsity? (Whether
truth and falsity are indeed polar opposites, as the princi-
ple of *bivalence implies, is itself a disputed issue.) At least
three candidates can be put forward: sentences, *state-
ments, and *propositions. Loosely, a sentence is a linguistic
token or type, such as the string of written words ‘This is
red’. A statement is the assertoric use of a sentence by a
speaker on a particular occasion. A proposition is what is
asserted when a statement is made—its ‘content’. Thus
two different speakers, or the same speaker on two differ-
ent occasions, may assert the same proposition by making
two different statements, perhaps using sentences of two
different languages. And the same sentence (conceived of
as a linguistic type) may be used in two different state-
ments to assert two different propositions.
In addition to speaking of sentences, statements, and
propositions being true or false, we also speak of beliefs
(and other *propositional attitudes) being true or false. So
is the notion of truth ambiguous, or is there a primary
notion which attaches to just one of these classes of items?
Opinions differ, but a broad division can be drawn
amongst theories of truth between those that regard truth
as being a property of linguistic or mental representations of
some sort—such as primarily sentences, statements, and
beliefs—and those that regard truth as primarily a prop-
erty of propositions, conceived as items that are represented
or expressed in thought or speech, but exist independently
of mind and language. Disputes between theorists of

truth are sometimes confused by a failure to discern this
division.
The best-known theory of truth is the *correspondence
theory. On this view, a candidate for truth is true if and
only if it ‘corresponds to a fact’. Some objectors complain
that the notion of a *fact is itself only to be explained in
terms of truth (for instance, as being the worldly correlate
of a true sentence or proposition), so that the theory is viti-
ated by circularity. Others complain that the notion of
‘correspondence’ is either vacuous or unintelligible. It is
hard to say which philosophers have really held this the-
ory. Aristotle is sometimes said to intimate allegiance to it
in his remark that ‘to say of what is that it is, and of what is
not that it is not, is true’. Wittgenstein’s ‘picture’ theory of
the Tractatus is often cited as exemplifying it. Even Tarski’s
*semantic theory of truth has been described as a version of
it. But in modern times its clearest advocate has perhaps
been J. L. Austin. The theory is often thought to be vulner-
able to devastating criticism in the form of the so-called
*slingshot argument. This argument seems to show that,
given any two truths p and q, the expressions ‘the fact that
p’ and ‘the fact that q’ must have the same reference, the
implication being that there cannot be more than one
fact—sometimes ironically called ‘the Great Fact’. The
problem is that correspondence theorists typically main-
tain that distinct truths correspond to different facts, but it
now appears that these supposed differences between facts
inevitably collapse. Very arguably, however, the proper
lesson to draw is not that there is something wrong with
the correspondence conception of truth as such, but rather

that not just its enemies but even some of its friends have
unnecessarily embroiled it in bad metaphysics.
Almost equally well known is the *coherence theory,
whose proponents are usually led to it by the perceived
difficulties of the correspondence theory. Accepting that
truth cannot consist in a relation between truth-bearers
and items which are not themselves truth-bearers (such as
‘facts’), these theorists propose instead that it consists in a
relation which truth-bearers have to one another—such
as a relation of mutual support amongst the beliefs of an
individual or a community. Opponents object that this
leads to an unacceptable *relativism about truth, since
many different and mutually incompatible systems of
belief could be internally consistent and self-supporting.
They also sometimes complain that advocates of the
926 Trotsky, Leon
theory are guilty of a confusion between stating a criterion
of truth—that is, a rule for the evaluation of a belief as
being true—and stating what truth consists in.
In order to overcome the objection of relativism, some
advocates of the coherence theory suggest that the notion
of truth is a regulative ideal, which could only be fully real-
ized in a unified and completed science far in advance of
the fragmented and partial belief systems of any human
community that actually exists or is ever likely to. In this
guise, the theory overlaps with some versions of the so-
called *pragmatic theory of truth, associated with the
American philosophers Peirce, James, and Dewey. The
latter theory—particularly in the hands of James—urges a
connection between what is true and what is useful, point-

ing out, for instance, that one mark of a successful scien-
tific theory is that it enables us, through associated
developments in technology, to manipulate nature to our
advantage in ways hitherto unavailable to us. Detractors
protest that this (alleged) conflation of truth with utility is
pernicious, because the ethics of belief require us to pur-
sue the truth with honesty even if its consequences should
prove detrimental to our material well-being.
All the theories of truth so far mentioned may be called
substantive or robust, as opposed to *deflationary, in the
sense that they all take truth to be a real and important
property of the items—whatever they are—that the theor-
ies take to be the primary bearers of truth. But in recent
times deflationary theories of truth have become quite
popular, the earliest example being the *redundancy the-
ory (a later variant of this being the so-called prosentential
theory of truth). This theory, building on the apparent
equivalence between asserting a proposition p and assert-
ing that p is true, holds that the truth-predicate ‘is true’
exists only in order to enable economy of expression, and
that what is said with its aid could in principle be said with-
out it. A closely related view is that the truth-predicate
plays a performative role, enabling speakers to express
their approval or endorsement of the assertions of other
speakers. Serious-minded philosophers will deplore such
views for taking truth to be so flimsy.
Some theorists in the pragmatic tradition, such as
Stephen Stich, now urge that truth as such has no cogni-
tive value—that we literally should not care whether our
beliefs are true or false, but only whether they enable us to

achieve more substantive goals such as happiness and
well-being. However, *Sophists were urging much the
same in the time of Plato and—fortunately!—it seems
unlikely that philosophers will ever entirely give up asking
‘What is truth?’ and assuming that the answer is some-
thing of importance. Quite apart from anything else, giv-
ing up the question of truth would deprive them of the
endless enjoyment to be derived from attempting to solve
the various paradoxes, such as the *liar paradox, which the
notion of truth throws up.
In recent years, metaphysicians have been emphasizing
again the connection between *realism and truth that
seems to have inspired many advocates of the correspond-
ence theory. This attitude often finds expression in some
version of the so-called truth-maker principle—the prin-
ciple that every truth (or, at least, every contingent truth)
must be made true by the existence of something in reality.
Some advocates of the principle, such as David Arm-
strong, maintain that truth-makers are states of affairs,
others that they are particularized *properties, or tropes.
So, for example, on the former view it is Mars’s being red
that makes true the proposition that Mars is red, while on
the latter it is Mars’s redness that makes this true. Both
approaches contend that the world contains a multiplicity
of truth-makers, but neither insists, as some versions of
the correspondence theory do, that there is a one-to-one
correlation between truths and truth-makers. Indeed,
truth-maker realism is not committed to the claim that
truth consists in, or is definable in terms of, any independ-
ently specifiable relation between truth-bearers and

other entities of any specific kind. For this reason, it is not
vulnerable to many of the objections traditionally raised
against the correspondence theory of truth, while at the
same time inheriting the attractive realist and anti-
relativist implications of that view. e.j.l.
*true for me; art and truth.
D. M. Armstrong, A World of States of Affairs (Cambridge, 1997).
S. Blackburn and K. Simmons (eds.), Truth (Oxford, 1999).
S. Haack, Philosophy of Logics (Cambridge, 1978).
P. Horwich, Truth, 2nd edn. (Oxford, 1998).
R. L. Kirkham, Theories of Truth (Cambridge, Mass., 1992).
R. L. Martin (ed.), Recent Essays on Truth and the Liar Paradox
(Oxford, 1984).
S. P. Stich, The Fragmentation of Reason (Cambridge, Mass., 1990).
truth, coherence theory of: see coherence theory of truth.
truth, correspondence theory of: see correspondence
theory of truth.
truth, deflationary theories of: see deflationary theories
of truth.
truth, double: see double truth.
truth, logical: see logical truth.
truth, pragmatic theory of: see pragmatic theory of truth.
truth, redundancy theory of: see redundancy theory of
truth.
truth, semantic theory of: see semantic theory of truth.
truth, subjective: see subjective truth.
truth and truthfulness. The assumptions that one is
truthful when speaking truly, and that truthfulness is a
virtue, because truth is valuable, are both questionable.
True statements can be intentionally misleading (e.g.

‘Someone stole your book’, said by the culprit), and a
would-be liar may, through ignorance, inadvertently say
something true. In neither case would we describe the
truth and truthfulness 927
speaker as being truthful. In The Gay Science (§344), Nietz-
sche denies that truthfulness is admired because it helps
disseminate truth, for ‘truth at any price’ may be ‘inimical
to life’. Rather, we admire truthfulness, irrespective of
practical benefits, on the ‘moral ground’ that ‘I will not
deceive, even myself’. The virtue of truthfulness is there-
fore relatively independent of the value of truth. d.e.c.
B. Williams, Truth and Truthfulness: An Essay in Genealogy (Prince-
ton, NJ, 2002).
truth-conditions. Usually short for ‘truth- and falsity-
conditions’. The truth-conditions of an indicative sentence
are the conditions under which it would be true, or false:
e.g. ‘I’m exheredated’ is true if the speaker is at the time of
speaking exheredated, and false otherwise. The truth-
conditions of a word or phrase are its contribution to
the conditions under which an indicative sentence con-
taining it would be true, or false: e.g. (for the word
‘exheredated’) any sentence ‘a is exheredated’ is true if ‘a’
in it refers to something exheredated, and false otherwise.
(These are very simple examples; even so, it is not implied
that they are necessarily accurate, especially over falsity.)
c.a.k.
D. K. Lewis, ‘General Semantics’, in Philosophical Papers, i (New
York, 1983).
truth-function. A proposition is a truth-function if
its truth-value is determined by the truth-value of its

components (or arguments). In the standard *propos-
itional calculus (PC), propositions have truth-values
True or False exclusively. The logical constants ~, ∨, ·,
⊃,
≡ (in one standard notation), which approximate to
the English ‘not’, ‘or (inclusive)’, ‘and’, a use of ‘if’, and ‘if
and only if’, respectively, are so defined that a *well-
formed formula of PC which is a proposition is a
truth-function.
For example, where φ and ψ are propositions,
~φ is true if and only if φ is false,
(φ ∨ ψ) is true if and only if φ is true or ψ is true or both
are true,
and so on as given in the *truth-tables for the logical con-
stants.
There is therefore an effective procedure for determin-
ing the truth-value of any PC proposition given the truth-
value of its basic (atomic) propositional components.
r.b.m.
B. Mates, Elementary Logic (Oxford, 1972).
truth-table. In the *propositional calculus, if φ and ψ are
propositions, then the truth-value True or False of the
truth-functions ~φ , (φ ∨ ψ), (φ · ψ), (φ
⊃ ψ), (φ ≡ ψ) may
be determined from the following matrices:
φ ~φ
TF
FT
φψ(φ ∨ ψ)(φ · ψ)(φ ⊃ ψ)(φ ≡ ψ)
TT T T T T

TF T F F F
FT T F T F
FF F F T T
where ‘~’, ‘∨’, ‘·’, ‘⊃’, ‘≡’ may be translated as ‘not’, ‘or’,
‘and’, ‘if . . . then – – –’, and ‘ . . . if and only if – – –’ respect-
ively.
The truth-value of truth-functions constructed out of n
basic (atomic) propositions can be determined from a
truth-table of 2
n
lines by systematic application of the
matrices.
For example, if p and q are basic or atomic propositions,
then the truth-table for ((p · q)
⊃ p) may be given as
follows.
pq((p · q) ⊃ p)
TT TT
TF FT
FTFT
FF FT
and translated as: If p and q, then p. r.b.m.
B. Mates, Elementary Logic (Oxford, 1972).
E. L. Post, ‘Introduction to the Theory of Elementary Propos-
itions’, American Journal of Mathematics (1921).
truth-value. The truth (T or 1) or falsity (F or 0) of a
proposition is its truth-value. In *propositional calculus,
propositions are regarded primarily as the bearers of these
two values: the *truth-table method is used to calculate
the value of compound expressions. Systems using more

than two such values have been developed by some
modern logicians, e.g.
Łukasiewicz. c.w.
A. N. Prior, Formal Logic, 2nd edn. (Oxford, 1962), pt. iii, sect. 2.
trying, or attempting; phenomenon whose relation to
*belief, *desire, *intention, is investigated in philosophy of
action.
Some philosophers accord trying a prominent role in
action’s elucidation, believing both that someone who
does something intentionally tries to do it, and that trying
marks a point where mental and physical concepts meet in
their application. A person’s trying to do something is nat-
urally thought of as ‘mental’; but an event of a person’s
trying to do something is, arguably, usually the same as a
‘physical’ action of hers. j.horn.
*volition.
Jennifer Hornsby, Actions (London, 1980), ch. 3.
Tugendhat, Ernst (1930– ). One of the most important
contributors to the re-establishment of *analytic philoso-
phy in Germany after the Nazi period, in which almost all
928 truth and truthfulness
analytic philosophers had to leave the country. Tugend-
hat, born in Brno as a Jew, emigrated to Venezuela,
received his BA at Stanford 1949, his Ph.D. in Freiburg
1956, and his Habilitation in Tübingen 1966. He has held
professorships in Heidelberg, Starnberg, and Berlin.
Trained by Heidegger in the Aristotelian and phenom-
enological tradition, he argues in an original way that ana-
lytic philosophy of language is the culmination of
Aristotle’s ontological project. Throughout Tugendhat’s

work the central characteristic of philosophy is ‘the idea of
organizing life as a whole in accordance with truth, i.e. the
idea of a life of critical responsibility’. Along the same
lines, he argues that Wittgenstein’s view of self-
knowledge and Heidegger’s account of practical self-
understanding are intrinsically connected because
consciousness of the self arises only when I ask the ques-
tion what kind of human being I aspire to be. This ques-
tion also plays a central role in ethics as Tugendhat
conceives it: morality can only be justified relative to con-
ceptions of good personhood. s.g.
E. Tugendhat, Traditional and Analytical Philosophy: Lectures on the
Philosophy of Language, tr. P. A. Gorner (New York, 1982).
Turing, Alan (1912–54). English mathematician best
known for the *Turing machine and the Turing test, both
concerned with the relation between computation and
mind. Turing’s work in mathematical logic in the late
1930s systematized ideas of Gödel and Church in the form
of an abstract description of what an idealized finite agent
could compute. During the Second World War Turing
worked on deciphering German codes, and in particular
on the computational machinery required. After the war
he worked on early digital computers and in 1950 pub-
lished ‘Computing Machinery and Intelligence’ in Mind.
In this article he proposes a test for thought: a machine can
think if its replies to questions are indistinguishable from
those of a human. a.m.
*computers.
Andrew Hodges, Alan Turing (London, 1985).
The Essential Turing, ed. B. J. Copeland (Oxford, 2004).

Turing machine. A Turing machine is an idealization of an
ideal finite calculating agent. It is usually described as if it
were a mechanism, but a description as an ideal clerk
would also be possible. So a Turing machine has an infin-
ite tape (or notepad), a head which reads or writes sym-
bols from a finite list to it (or pen), and a finite number of
states. A machine-table specifies what, given a state and a
symbol, will be overwritten at that point, and the next
state. It can calculate anything any digital computer can.
Three fundamental facts are (a) the characterization does
not depend on details of how many symbols etc. there are;
(b) there is a ‘universal’ Turing machine which can mimic
the output of any other machine; (c) there is no Turing
machine which, given a specification of any arbitrary Tur-
ing machine and an input, will halt when that machine
halts, given that input. The last, (c), is closely related to
Gödel’s theorem. Turing machines can give substance to
*functionalism in the philosophy of mind. a.m.
*computer; Gödel’s theorem.
George Boolos and Richard Jeffrey, Computability and Logic, 3rd
edn. (Cambridge, 1990).
The Essential Turing, ed. B. J. Copeland (Oxford, 2004).
Twardowski, Kazimierz (1866–1938). Polish philosopher
who became the father of Polish *analytic philosophy.
Twardowski studied in Vienna with Brentano (Ph.D.
1891, Habilitation 1894). In 1895 he was appointed a pro-
fessor of philosophy at the University of Lvov. Twar-
dowski was a distinguished teacher who trained many
Polish philosophers and logicians, including Ajdukiewicz,
Kotarbin´ski, Les´niewski, and

Łukasiewicz. In his essay
Zur Lehre vom Inhalt und Gegenstand der Vorstellungen (1894)
Twardowski introduced a distinction between the con-
tent and the object of presentations which completed
Brentano’s earlier analysis of psychic phenomena in terms
of acts and objects. Twardowski also argues for the thesis
that there are no objectless presentations and develops a
theory of objects. His Habilitationsschrift considerably
influenced Meinong’s ontology and Husserl’s preparatory
studies to Logische Untersuchungen. The actions–products
distinction is another of Twardowski’s conceptual clarifi-
cations which deserves to be mentioned. j.wol.
K. Twardowski, On the Content and Object of Presentation, tr.
H. Grossmann (The Hague, 1976).
twin earth. Imaginary counterpart to earth introduced in
thought experiments in philosophy of mind and language.
In Putnam’s famous example, on twin earth the stuff
which falls from the sky, comes out of taps, and consti-
tutes oceans, etc. is XYZ, not H
2
O. Putnam argued that a
person’s meaning what she does cannot be ‘in her head’,
since twin earth’s inhabitants’ heads are not relevantly dif-
ferent from earth’s, but what they mean by ‘water’ is dif-
ferent from what earth’s inhabitants mean. j.horn.
John Heil, The Nature of True Minds (Cambridge, 1993), ch. 2.
two-envelope paradox. Imagine that you are offered a
choice between two envelopes, each containing money.
One has twice as much money as the other, but you are
not told which. Once you have selected an envelope, A,

you are offered a further choice. You can either open the
envelope or swap it for the other, B. You reason as follows.
Let the amount of money in A be x. The other envelope, B, con-
tains either 2x or x/2. The two possible outcomes are equally
probable. Therefore, the expected value of swapping A for B is
(0.5 × 2x) + (0.5 × x/2) = 5/4x. Since the expected value of hang-
ing on to A is x (given that it is certain that A contains x), if I want
to maximize expected value, I ought to swap A for B.
This is paradoxical because, once I have swapped A forB, a
similar line of reasoning will show that I ought to swap
back—and so on indefinitely. j.ber.
*decision theory; paradoxes.
two-envelope paradox 929