Last week, I wrote about the problem of relying on the
information we get from a few select individuals in the reporting
world. This is especially a concern when many in the media seem to
lack any sort of moral devotion to their profession. I decided to
follow that piece up (and indulge myself) with a broader
investigation of knowledge and doubt. If you like this sort of
thing, read on.
“Skepticism,” said the 18th century philosopher David Hume, “is
a malady which can never be radically cured, but must return upon
us every moment, however we may chase it away.”
Certainly, we can trust Hume as an authority on the subject if
we can trust anyone. In the course of his rigorous philosophy he
was able to offer compelling and sound arguments against many of
the things we most take for granted: the existence of matter, the
law of cause and effect and even the self.
But speaking more generally, is it true that we are faced with
skepticism every moment of our lives? Is it true, as some have
maliciously argued, that the world is only an illusion and true
knowledge is impossible?
One’s initial reaction to this sort of proposition is a
common-sense one; of course knowledge is possible, we say. There
would, for example, be no foundation for a university if knowledge
was not obtainable. On the surface, this belief in the reality of
knowledge seems to make philosophical skeptics look merely foolish,
or, at the worst, dangerous.
To truly understand the problem of skepticism, though, I think
we have to look beyond what our intuition and “common sense” tells
Consider, first, that everything we claim to know about the
outside world comes to us by means of our five senses. The question
that arises immediately from this fact is: how do we know our
senses are accurately reflecting the world? How do we know, for
example, that we are not merely brains in a vat somewhere with
electronic signals being pumped into our cerebrum to give us the
illusion of physical existence?
This “Matrix”-esque situation, however, does not exhaust the
possibilities. For one thing, it presupposes the idea that there
are actually things called brains and that what we call “sensory
perceptions” actually exist.
Certainly, there is no empirical way to verify the correctness
of what we perceive. People attempt to argue against this by
postulating the existence of other beings with which we can reach
consensus, and therefore conviction about sensory things.
For example, if I see an apple and another person tells me they
see it as well, I assume that this somehow proves the existence of
the apple. But the status of the supposed “other person” is the
same as that of any other thing in the outside world; that is, they
only exist as a function of my sensory interpretation of the world.
Ever since Descartes declared “I think, therefore I am,” the mind
has been set off against the outside world as self-evident.
It can be seen, then, that there is absolutely no way to prove
the existence of such a thing as the outside world. There are
truths we can legitimately call absolute, however.
For example, that 2 + 2 = 4 is a true proposition is something
that can not be argued with. It is in the very nature of these
conceptual entities – i.e. “2”, “4”, and the addition symbol – that
they yield this sum when combined in this manner. Even if no
numerals existed this would be the case.
To take another example, it is not possible to deny the
existence of circularity as a concept. Even if the material
universe did not exist and we had no word for circle, there is the
logical necessity of a conceptual object in which all points on the
outside of the shape lie at equal distances from the center. To put
this another way, try to imagine a square circle. One can not do it
of course, for the two are logically contradictory – this is
because of the logical necessity of a circle’s incompatibility with
Thus, we can have knowledge at least in the sense of
understanding logical relations. But this does not answer the
question of how I can know that the pizza I am eating or the girl I
am kissing is not merely a figure in a dream, or that my entire
life is not merely a passing thought in the mind of an old man.
Still: when I go out into the world, I will adhere to the laws
of science and treat my friends as the same people they were
Can I prove the validity of either of these actions? As I
already argued, this is impossible, but then again it may not be
necessary. Whatever the ontological status of the pizza I will eat
tonight, I can still believe that it tastes good. The entire span
of our lives, it seems, is practiced according to this same naive
Brent is a freshmen studying philosophy, surpisingly.