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PARTISAN REVIEW
result was, as he engagingly remarks, fortunate in view of the intrac–
tability of the problem of free will.
In
such a situation many authors
would have set the original project aside and mined gold where they
found it, but Nozick is ready to give us his ideas even where he him–
self finds them unsatisfactory or at least inconclusive, and it is not,
therefore, surprising that he is not always writing at his best.
Where he is at his best Nozick is really good. The discussion of
knowledge and skepticism opens with a skeptical argument against
the possibility that anyone knows anything.
You think you are seeing these words, but could you not be hal–
lucinating or dreaming or having your brain stimulated to give
you the experience of seeing these marks on paper although no
such thing is before you? More extremely, could you not be float–
ing in a tank while super-psychologi ts stimulate your brain elec–
trochemically to produce exactly the same experiences as you are
now having, or even
to
produce the whole sequence of experi–
ences you have had in your lifetime thus far?
If
one of these other
things was happening, your experience would be exactly the
same as it now is. So how can you know none of them is happen–
ing? Yet if you do not know these possibilities don't hold , how
can you know you are reading this book now?
If
you do not
know you haven't always been floating in the tank at the mercy
of the psychologists, how can you know anything-what your
name is, who your parents were, where you come from ?
Nozick then proceeds to give us a most interesting, clever, and
ingenious solution to the problem of how knowledge can neverthe–
less be possible. What, he asks, are the conditions for knowledge?
What must be the case if one is not just to believe some true proposi–
tion but to
know
that it is true? As Plato pointed out so long ago,
knowledge is not simply true belief; and the relation of knowledge to
true belief is a topic much canvassed at the present time. Given that
one may come
to
believe something that happens to be true, but
may believe it for reasons that have nothing to do with its truth ,
some extra condition beyond true belief is necessary for the existence
of knowledge. What is this condition? Nozick thinks that someone
who has a true belief
knows
that which he believes only if his belief
"tracks" the fact with which it is concerned. !fone knows that a cer–
tain proposition is true, one's belief that it is true is not coincidental
but rather dependent on this truth. And this dependence must be
