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needed for the truth to emerge in the course of time is aborted. Yet, on
the other hand, toleration for the intolerant can be self-defeating.
Popper writes: "If we concede to intolerance the right to be tolerated,
then we destroy tolerance and the constitutional state. That was the fate
of the Weimar Republic."
In contrast to both Ayer's and Popper's books, the style, method
and issues found in Quine's
Pursuit oj Truth
appear to be continuous
with the primary interests of the Vienna Circle. Yet his ongoing revision
of the original positions, the breakdown of all inherited rigidities and
the rigorous flexibility he pursues, demonstrate how great is the distance
both logic and the analysis of the language of science have traversed
through the decades. For Quine, even the formal, definitional or logical
parts of a scientific language are not totally immune from revision in the
light of experience. There is a difference between analytic and non-ana–
lytic statements, but it is one of degree and is context dependent.
Empirical sciences develop and are verified by our ability as human beings
to use the sensory stimuli of the environment as evidence for our hy–
potheses about the world. He asks:
From impacts on our sensory surfaces, we in our collective and cumu–
lative creativity down the generations have projected our systematic
theory of the external world. Our system is proving successful in
predicting subsequent sensory input. How have we done it?
In this tightly-packed volume, Quine goes on to clarify many issues
that arise in the interpretation of the nature of scientific inquiry. In a
statement which has special relevance to the theme of the rise, fall, and
transformation of logical positivisim, Quine writes of science as a
"language game":
But when I cite predictions as the checkpoints of science ...
I
see it
as defining a particular language-game in Wittgenstein's phrase: the
game of science in contrast to other good language games such as
fiction and poetry.
A
sentence's claim to scientific status rests on what
it contributes to a theory whose checkpoints are in prediction.
Quine proceeds to discuss the nature of "reference" in the language
of science. He seeks to explain what kinds of things can be said to exist
in a scientific theory. His most famous summary answer is the formula
that "to be is to be the value of a variable." In
Pursuit oj Truth,
the
