[This is a continuation of a thread begun here.]
Another example of fetishizing the visible (cf. now also this) occurs in Karl Popper’s Conjectures and Refutations: the Growth of Scientific Knowledge (1962; page refs. to the Harper paperback reprint), p. 284:
In the last pages of Testability,
Carnap discussed the sentence ‘If all minds should disappear from the
universe, the stars would still go on in their courses.’ Lewis and
Schlick asserted, correctly, that this sentence was not verifiable.
They
so asserted incorrectly. After all, we have a pretty good handle on
those stars in their courses, beginning from not long after the Big
Bang through the present, during most of which there were no human
minds.
And
here’s a simpler experiment: Let’s all just refrain from observing the
moon for the next two weeks. Now we open our eyes. Surpri-ise! Right
where we expected to find it, and at a phase two weeks more mature than
when we last checked (rather than the phase as last seen).
One
occasionally observes a very young child shut her eyes and announce in a
sing-song: “Youuu ca-han’t seee mee….!” I doubt the child actually
believes that, it’s just fun to say. But suppose she did. She is then
entertaining an erroneous optical theory, but not an erroneous
ontological one. She imagines that the lights went out for you as well;
but she never entertains the thought that you yourself have been
extinguished, or been transfixed into some mute deaf motionless limbo
until such time as she shall be pleased to gaze again – after all, she
has just shown this, by addressing you.
Incidentally,
the whole Schlick-shop with its merry/morose band of logical
positivists, appear to have created enormous problems for themselves,
and come up with completely counter-intuitive results, from the basic
motivation of wishing to exclude all metaphysical propositions from the
outset as strictly meaningless. (The story here is in line with our
overarching defense of theism.) In other words, it wasn’t enough to
denounce as wholly unconvincing, all purported metaphysical statements
hitherto; nor to brand it a particularly uninteresting language-game;
nor to marginalize the enterprise with the derision usually reserved for
circle-squarers. Metaphysics as such, and for all time, had to have a
stake driven through its heart, the stake itself consisting in pure
reasoning from selbstverständlich
(metaphysically a-priori? God-given? -- oops, NOT) first principles.
For a demonstration of the absurdities that apparently resulted, cf.
Popper, passim. As (p. 281, op.cit.)
My criticism of the verifiability
criterion has always been this: against the intention of its defenders, it did
not exclude obvious metaphysical statements, but it did exclude the most
important … of all scientific statements … the universal laws of nature.
Why even go near such a disaster, for the sake of
excluding-in-principle all metaphysical statements – which they were ignoring
anyway? Popper goes so far as to
hazard a guess in a footnote to p. 175:
“One not need believe in the ‘scientific’ character of psycho-analysis
(which, I think, is in a metaphysical phase) in order to diagnose the
anti-metaphysical fervour of positivism as a form of Father-killing.” (Note, b.t.w., the capital initial of
“Father”.)
*
Since
we were obliged, a moment ago, to deprecate Popper, let us hasten to
another example, in which we find him on the side of the angels. First
let us note:
* Our conduct is guided by moral laws.
* Our scientific activity is guided by metaphysical principles.
* Both categories are philosophically vexed, and any concrete
application of these laws and principles may prove problematic; but we
cannot do without them.
Here is Popper (p. 287) characterizing the logical positivists: “They
implicitly accept the rule: ‘Always chose the most probable
hypothesis!’ He goes on:
Now
it can be easily shown that this rule is equivalent to…’Always choose
the hypothesis which goes as little beyond the evidence as possible!’
And this, in turn [amounts to] ‘Always choose the hypothesis which has
the highest degree of ad hoc character!’
an
undesirable result for science. (Cf. Chomsky, passim, re the
extraordinarily abstract and roundabout way you may have to proceed to
get valid results, by no means simply tip-toeing a bit beyond “the
evidence”.)
The principles which we require instead may be best illustrated by an
old joke (presented here in a slightly revised form):
A zoologist, a mathematician, and a positivist are touring the
hinterlands of Bohemia by train. Through the window they spot, standing
motionless at some distance, a purple cow.
“Fancy that!” exclaims the zoologist. “There are purple cows in Bohemia.”
The mathematician, in a low voice, amends: “There is at least one purple cow in Bohemia.”
The positivist, raising his finger, crisply corrects to: “In Bohemia there is at least one cow, purple on one side.”
The joke is that the positivist has the most precise view of the
evidence; and of the three statements, only his own is certainly true
(interpreting an unmodified “purple cow” in the natural way, as “purple
more or less all over”); yet his scruples are absurd. Science would not
progress, were it bound by such fragmented literalism. (Indeed, we
should have to replace “cow” with “an apparently bovine organism”, and
always assuming that we can rule out a mirage, or a collective
hallucination, or some effect of swamp gas; or for that matter an
analogue to one of Hilary Putnam’s pet entities, the Mechanical Cat from
Mars.) And we would have to gloss Quine’s celebrated interjection, gavagai!, as possibly: “Lo, a rabbit-stage, seen from the east.”
Note:
Occasionally one meets with such unilateral positivist agnosticism in a non-jocular context:
Franz Ferdinand rode erect, his visible foot deep in the stirrup, a
saber at his side.
-- Robert D. Kaplan, Balkan
Ghosts (1993), p. xxvi
The
above scenario has been much discussed among epistemologists, under the rubric “Henry
and the barn façades”. However, the cow version is much
funnier.
Ceci n’est pas une grange |
~
To move from this to an outlook useful for science, we need these metaphysical principles:
(1) a certain uniformity or self-cohesion to nature
(2) the reliability (not in a logical, but in a practical sense) of induction.
(There are others, of course, such as the usefulness of deduction; but that applies in every world, not just in this contingent one.)
Now, both these principles are of vexed and delicate application; as
are, indeed, the Commandments. Just as it is difficult to avoid
situation ethics, I see no way around a kind of “situation
metaphysics”. The zoologist, using these principles, together with his
discipline-specific knowledge (to the effect that animals generally
come in species, not as singletons), concludes the presence of purple
cows. But here I must side with the formulation of the mathematician:
there is at least one such cow, but perhaps no more. For, nature’s
uniformity depends on the domain. Were an experiment ever to identify,
say, a Higgs boson, we should conclude the existence of an emphatic
plurality of Higgs bosons; that there should only be one in the
universe, is inconceivable. But biology is more mottled than that.
Given our collective prior acquaintance with hundreds of thousands of
cows, none of which was ever purple, we would hypothesize here an
extremely rare mutation for (bilateral) purple (bilateral because
bilaterally symmetric animals generally continue to evolve with
bilateral symmetry, pace
the occasional narwhal). Since a cow delivers but a single calf at a
time, this one has no identical siblings, so it is probably unique.
Moreover, the bulls will likely shun her for her color, and she shall
have no offspring. The mutation dies with her.
Carnap
attempts to avoid the assumption of a metaphysical principle, by
declaring (1) to be “analytic” (i.e., more like “2+2 = 4” than like
“animals tend to come in species” or “each elementary particle is
invariable within its class”). Popper comments (p.289) that “no such
principle of uniformity can be analytic (except in a Pickwickian sense
of ‘analytic’)." In fact, we noticed, the principle is nothing remotely
like analytic, having always constraints on its application, which in
some domains may be severe. And as for (2), I concur with Popper
(p.292) that it is “a principle of a priori metaphysics.” And none the worse for that.
[For further notes on ineluctable metaphysical underpinnings of the scientific enterprise, see here.]
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