It would not be an exaggeration to say that the distinction between
appearance and reality is, and has always been, one of the principal
focal points of philosophy. Although the question relates to intricate
relationships among theories of knowledge, ontology, and truth, the
chief question raised by the distinction is epistemological: How can
people know the nature of reality when all that people have immediate
access to are appearances? Broadly speaking, responses to the question
fall into one of three classes: Those that argue that observers are
unavoidably "cut off" from reality, those that argue that there is some
way of "getting at" reality through the appearances, and those that
reject the distinction. This article will examine some of the most
prominent statements of each position. Surveying these positions will
illustrate the way in which any approach to the issue forces a
philosopher to take a stand on a wide set of philosophical issues, which
explains why the distinction has formed a starting point for many of
the greatest philosophical systems in the history of Western philosophy.
Motivation for the distinction
There are both common-sense and historically contingent sources of
motivation for the distinction between appearance and reality.
Because of everyday experience, people frequently find themselves in
situations where they are presented with appearances known to be
misleading. Some instances of this are dramatic, such as crafted
perceptual illusions that immediately come across as unbelievable. In
other cases, the knowledge that the appearances are misleading requires
more experience and investigation (e.g. rainbows). In general terms,
these are cases which one can report in a sentence of the form, "It
seemed to me that P, but really, it's not the case that P." Further,
one might compare two instances where things seemed to be the same way,
whereas there was a difference in reality. One way to report that would
be to say that the appearances were the same in both instances, though
the underlying reality differed.
Though the above motivations for the distinction are common to all human
experience, philosophical discussions of the distinction have been
fueled by scientific advances which seemed to yield the result that
certain features of experiences are only "appearance-deep." The gradual
acceptance of Copernicus' heliocentric model of the solar system in the
sixteenth and seventeenth centuries came with the realization that the
apparent rising and setting of the sun were, in fact, illusions. This
fact made a deep impression, and lead towards a new philosophical
picture of the universe in which things like colors and sounds were
deemed "mere appearances," while only properties susceptible to
geometric analysis (such as shape and motion) were kept as part of the
picture of true reality.
More recent developments in science have had similar effects. Einstein's
theories of relativity, as well as advances in quantum mechanics, have
led some scientists and philosophers to claim that even
three-dimensional space and a universal, uniform temporal structure are
mere appearances. Various feminist and postmodernist thinkers have gone
so far as to claim, sometimes on the basis of scientific advances, that
objective reality itself is, to some degree, an illusion (for an
important clash between those thinkers and their philosophical
opponents, see the debate ignited by physicist Alan Sokal's 1996 Hoax).
The actual argumentative path between the scientific advances and such
conclusions is extremely subtle, however. It is a matter of substantive
debate whether or not the fact that a given scientific model has a
certain type of explanatory power, which implies that it tells
scientists something about which objects or properties are real and
which are merely apparent.
Skeptical responses
When faced with the distinction between appearance and reality, and the
worry of how one can know reality on the basis of the appearances with
which one is presented, the most straightforward response may be to
simply deny that people have any reliable access to reality. This sort
of position is often described as "skepticism."
In the Hellenistic period in ancient Greece, there were two prominent
schools of thought which identified themselves as skeptics: The
Academics and the Pyrrhonists. Both drew inspiration from the early
dialogues of Plato, which typically involved the character Socrates
demonstrating that someone who claimed to be an authority on a certain
subject in fact had no knowledge. The Academics believed that the gap
between appearance and reality was, in principle, unbridgeable—no claims
concerning reality itself, other than its unknowability, were
permissible. The Pyrrhonist position was somewhat weaker, for they made
no claims to certainty about the nature of the gap. Instead, they aimed
for a practical ideal, in which one refrained from all judgments, and
so would never affirm something false.
Ancient skepticism exerted great influence on later European philosophy.
Descartes and Berkeley proposed philosophical systems aimed at
combating skepticism (see below), while others such as Pierre Bayle took
on the task of defending it. Skepticism of some form or another
remained a central topic in twentieth century epistemology, as witnessed
by the work of philosophers such as Peter Unger.
Epistemically-Optimistic Responses
Plato
Before the development of skepticism as a general school of thought, the
Athenian philosopher Plato offered a classic articulation of the
appearance/reality distinction, while indicating what he found to be the
way to achieve knowledge of reality. Plato's picture is a rationalist
one, relying on a faculty of reason that was independent of the senses,
and articulated the basic elements of the philosophical systems of later
thinkers such as Descartes and Leibniz.
In Book VII of his Republic, Plato presents "The Allegory of the
Cave." The Allegory begins by describing what Plato takes to be an
analogue of the epistemic position in which the majority of people
belong to: People are inside a cave, facing away from a fire, and see
only the shadows of objects which are moving behind them. Because they
see nothing other than these shadows, they mistakenly assume that these
shadows are real objects, and put much effort into watching them and
discovering their details. Yet, Plato asserts, it is possible for
someone to escape this position and leave the cave. Such a person would
at first be blinded by the light of the real sun, yet would start
acquiring knowledge of true things and realize the absurdity of the
shadow-examination that continues in the cave.
Explaining the meaning of each of the elements of the Allegory is a
significant interpretive challenge, but the basic ideas are
straightforward. The shadows correspond to the appearances with which
our senses present us. The aspect of the story where the shadows are
generated by objects illuminated by a light other than the sun is meant
to indicate that they are somehow produced by real things, but in a very
indirect manner. Leaving the cave is meant to correspond to a
philosopher's ability to cease relying on his senses as a guide to
reality and instead use his faculty of reason. Reason not only puts him
in epistemic contact with the true elements of reality (the "Forms" of
Plato's metaphysics), but also allows him to understand the degree to
which appearances differ from these elements, and how they are produced
by them.
What is distinctive about Plato's approach to the appearance/reality
distinction, especially in contrast to later figures, is the degree of
distance by which he believes appearances are separated from reality.
Reality, for Plato, isn't composed of the sort of things one might have
intuitively thought it was, such as particular rocks and animals, but
rather of a set of "pure" objects knowable by philosophical inquiry
(such as "the Beautiful itself" and "the Good itself"). Putting the
matter somewhat loosely, it might be said that Plato presents a
philosophical system in which observers are able to understand reality
through (or despite) appearances simply because reality is just the sort of thing one's intellect is capable of uncovering.
Descartes
In the Modern period of philosophy, the canonical expression of the
distinction between appearance and reality, and of the ensuing threat
posed to knowledge, is found in Rene Descartes' Meditations on First Philosophy
(originally published in 1641). Descartes highlighted the distinction
with a simple but powerful imaginative project. He asked how much
divergence there could conceivably be between the appearances he
encountered and the world in which he existed. The answer is made vivid
by his description of a scenario in which he is the subject of
deliberate and near-complete deception by a powerful "evil genius" (see
Meditation I), a scenario which no appearances give him any grounds for
ruling out as a genuine possibility.
Descartes eventually concludes that the gap between appearance and
reality is surmountable, and that he can rule out the evil genius
scenario. He reaches this conclusion by arguing from the fact that he
has an idea of an omnipotent, benevolent God to the existence of
that God, and then by arguing from the existence of such a God to two
claims: (1) since God is responsible for the world and its appearances,
it would be incompatible with God's goodness if there were to be a
dramatic difference between the two, and (2) since God is responsible
for Descartes' own faculties, he must be capable of knowing the truth
about the world around him.
Though Descartes' arguments made a massive impact on the philosophical
landscape, they were by no means universally accepted. There is a
general agreement that his proofs for God's existence are much less
compelling than he took them to be. Yet, for those who continued to
accept the fundamental distinction in Descartes' terms, it was unclear
what else besides a knowable, benevolent God could fill the needed role.
Kant
Over a century after the publication of Descartes' Meditations, a
more subtle answer to the problem was provided by Immanuel Kant, one
which would inspire the tradition known later as "German Idealism" (to
be contrasted with the idealism of Bishop Berkeley, discussed below).
Kant appears to accept something like Descartes' distinction, yet he
poses the issue in terms of an opposition between "objects as they
appear" and "objects as they are in themselves." Observers have no real
knowledge of objects as they are in themselves, Kant claims, but it was
a mistake on Descartes' part to think that they ever wanted such
knowledge. Properties like spatial extension, temporal duration, and
causal connection, Kant argues, properly belong to the realm of
appearances. Because appearances are in some sense "in us," and people
are capable of knowing themselves, this opens the possibility of knowing
whether objects really are spatially extended, causally related, etc.
Kant holds that much of reality remains unknowable, yet he takes this to
be a desirable result, for it precludes scientific
considerations (which only concern the appearance-based properties of
objects) from ever ruling out freedom of the will or the existence of
God, even while the actuality of the latter two remain unknowable.
In twentieth century philosophy, a number of related responses have been
considered. One particularly noteworthy suggestion is that, as things
are, what humans lack is not knowledge of reality, but knowledge that we
have such knowledge.
Responses that reject the distinction
Berkeley
The Irish Bishop George Berkeley, like Descartes, saw skepticism as a
serious, but surmountable, philosophical threat. Unlike Descartes,
however, Berkeley believed that it was a mistake to distinguish
appearances from reality in the first place. Following his predecessor
John Locke, Berkeley puts the discussion in terms of "ideas," where
these include both the appearances one encounters in sensory perception,
as well as the mental entities involved in one's thoughts. Berkeley's
fundamental claim (developed in his Principles of Human Knowledge (1710) and in his Three Dialogues between Hylan and Philonous
(1713)), was that all that exists are minds and the ideas they have.
Skepticism about the external world, he argued, arose from a wholly
unwarranted positing of "material substance," understood as something
distinct from ideas and minds, which is somehow represented by ideas and
thereby mediately encountered by minds. Once observers assume such
things exist, and that they are the objects of one's knowledge, Berkeley
believes that people will inevitably conclude from the mediacy of their
awareness of those objects to a lack of true knowledge on the
observer's part.
Yet, Berkeley argued, it was an unwarranted break with common sense for
philosophers to assume the existence of material substance, and in doing
so to create the distinction between appearance and reality. The
objects that populate the world aren't something to be accessed by means
of ideas, rather, they are those ideas. Berkeley has a simple argument for this claim:
- People perceive objects immediately.
- The only entities people can perceive immediately are ideas.
- Therefore, objects are ideas.
Berkeley's system is strikingly elegant. Unsurprisingly, however,
he is hard-pressed to account for the phenomena that originally
motivated the distinction, such as perceptual illusions and scientific
advancement. Ultimately, Berkeley appeals to God, as causal source of
the ideas, who maintains a certain order among them that one can only
gradually come to understand.
Reid
While Berkeley rejected the appearance/reality distinction by making
reality more mental (and so, in a sense, claiming that all there is are
appearances), others have rejected the distinction by attacking the
notion of "appearances" or "ideas" that is in play. Antoine Arnauld
argued for such a position in the wake of Descartes' Meditations,
but the first sustained attempt to develop the position came from
Thomas Reid, a Scottish minister and professor. In the second essay of
his Essays on the Intellectual Powers (1785), he specifically
attacked the intelligibility of the "ideas" assumed by Locke and Reid,
and attributed philosophical worries about the gap between appearance
and reality to the assumption of such mental entities. When one
perceives an object, Reid claimed, they do so directly, not by
means of any idea or appearance. Such ideas would amount to a veil
between observers and the world, whereas in truth there is no such
barrier. Like Berkeley, however, Reid was hard-pressed to explain away
illusions, and ultimately ended up assuming the existence of
"sensations"—mental entities with some similarity to Lockean ideas.
Nevertheless, many contemporary philosophers have found his attempt
compelling.