Positivism vs Realism

Tom DiBenedetto tdib at UMICH.EDU
Mon Dec 15 08:32:12 CST 1997

James Francis Lyons-Weiler wrote:

>The confusion on boldness is still there for you, T.

I guess we will have to disagree on this. Since I gave you a rather
unambigous Popper quote (two times) and since Popper is the one who
brings the term into the
debate, I'll be content to stick with that.

>Whenever an ad-hoc
>hypothesis is concocted to save a previously rejected hypothesis (and that
>is the order in which it occurs - NOT simultaneously), that hypothesis
>cannot be tested - we agree to that much.

No we dont. Untestable hypotheses are metaphysical statements; see
Popper's discussion of demarcation (his point of entry into this
whole subject). Ad hocs are within the realm of scientific
statements, hence testable, but only minimally so.
You are right that in principle the ad hoc is concocted afterward (in
systematics of course, we have convergence already in mind as a ready
alternative), but we could substitute a testable ad hoc hypothesis.
It would not say much, would not be very testable or corroborable,
but it could conceivably be testable.

>  Now consider that technological
>advances make the hypothesis testable - according to your interpretation
>of "boldness", before the technology, it was not bold; after the
>technological breakthrough, it is.  This seems illogical.

That is not what I said, I said that boldness is a function of how
much it says. How much it says defines its testability. If technology
makes its testability practical, so much the better. E=mc2 would have
been bold if Newton had come up with it, because of what it tries to
say. It would have been as testable as now,,,,in principle.
Technology makes it practically testable now.

> The empirical
>content of a hypothesis and the degree to which it extends beyond accepted
>facts is a characteristic that doesn't change - it is (supposed to be) a
>rather straigtforward feature of a hypothesis -

fine, not inconsistent with what I say.......

> Popperian was well aware that some
>ad-hocs will eventually become testable - and the formal logical allocates
>just as much boldness to a hypothesis whether it is testable or not (at
>time t).

at time t  - ok  that is simply the practical issue. We have been
discussing testability in principle.

>It's like potential energy.  This rock would surely release a lot a
>potential energy IF it is pushed off a cliff.  The energy is there whether
>the rock pushed or not.

fine, I dont see much use in pushing you off your analogy. Just bear
in mind that ad hocs have minimal testability because they say very
little, and that bold hypotheses have maximal testability because
they say a lot. In principle.

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