Intelligent Design: Affirming the Consequent

Hello,

Here is a draft of something I began to think about while reading a
chapter in a book on the philosophy of science. I think it is a good
argument undermining the claim that ID is real science.

Comments and criticisms are most welcome.

Regards,
Shepherdmoon

=======
Intelligent Design: Affirming the Consequent

The logical fallacy of affirming the consequent is explained as
follows:

---
Affirming the consequent is a logical fallacy in the form of a
hypothetical proposition. The fallacy of affirming the consequent
occurs when a hypothetical proposition comprising an antecedent and a
consequent asserts that the truthhood of the consequent implies the
truthhood of the antecedent. This is fallacious because it assumes a
bidirectionality when it does not necessarily exist.

This fallacy has the following argument form:

If P, then Q.
Q.
Therefore, P.
---
http://en.wikipedia.org/wiki/Affirming_the_consequent

Here is an example from a book on the philosophy of science:

1. If a man takes arsenic (P), then he will die (Q).
2. A man dies (Q).
--------------------------------------------------
Therefore the man took arsenic.

Source:
Peter Caws, The Philosophy of Science. New York: D. Van Nostrand
Company Inc., 1965, p. 111.

This example commits the fallacy of affirming the consequent because it
takes a consequence -- a man dies -- and infers that consequence as
evidence in favor of the hypothesis that arsenic was the cause of
death. But not every man dies from arsenic poisoning, so the inference
on the basis of the consequence alone is invalid.

Intelligent Design proponents commit the fallacy of affirming the
consequent each time they claim that their observations of the
complexity of life justify the inference to intelligent design.

The ID version of the fallacy is:

If life is the product of intelligent design (P), then life will
exhibit complexity (Q).
Life exhibits complexity (Q).
--------------------------------------------------
Therefore life is the product of intelligent design (P).

The problems with this reasoning are:
1. It is logically fallacious, since it is of the same form as, for
example, the arsenic fallacy illustrated above.
2. It is trying to use an observation to verify the hypothesis of
intelligent design by using only the consequence, a consequence for
which other hypotheses (for example, naturalistic evolution) may be
true.
3. It gives no hypothesis for the cause of the complexity (the
intelligent designer), and so would not be useful even if it were
presented in correct logical form.

Thus the ID argument has no logical truth or scientific value to it, at
least as it is currently formed.

It is very likely that ID proponents will immediately counter that a
lot of scientific reasoning operates according to the fallacy of
affirming the consequent. Indeed, in the book above, the author points
out that "This [affirming the consequent] is in fact the argument we
use most frequently in justifying scientific hypotheses..." (Caws, p.
111).

However, that is why scientists do not rely on verification alone, as
the ID argument does. Caws points out that science uses *falsification*
to change the above reasoning into a logically valid form (presented
below based on Caws, p. 112).

If P, then Q
Not Q
---------------
Therefore not P

In this form, the hypothesis "may be *falsified* conclusively if the
consequences fail to occur" (Caws, p. 112). The point is not that
science can conclusively establish the final truth forever, but rather,
that employing falsification enables scientists to better eliminate
hypotheses that don't work and thereby evaluate the confidence with
which to accept a hypothesis (Caws, p. 112).

Despite a lot of public relations resources spent by ID proponents to
convince the public that ID is the same as real science, I think that
ID is different in this crucial respect.

Unlike real science, ID commits the fallacy of affirming the consequent
and then sticks with it. Affirming the consequent makes up the bulk of
the ID argument, since ID proponents specifically refuse to hypothesize
about the designer they infer. But by that refusal, ID proponents also
prevent the formation of a scientific ID hypothesis. To make a
scientific hypothesis is to make a positive statement that can be
subjected to scrutiny. Real science requires putting a proposed cause
out there with the risk that it will be falsified.

That is why evolutionary biology is real science. It proposes specific
causes -- random mutations and natural selection, knowing that its
propositions may be falsified -- but also knowing that with
falsification comes further knowledge about how the world really works.


IDers, by contrast, protectively shield the intelligent designer from
falsification by trying to keep the designer out of the discussion. Yet
by excluding the designer, IDers have nothing more to propose than the
fallacious reasoning described above. And because it is highly unlikely
that IDers will change their strategy of refusing details about the
designer, that is a strong rational argument for keeping ID out of
science classes. Without a falsifiable hypothesis about the designer,
there is no science in ID to teach.

.

Relevant Pages

  • Re: Intelligent Design: Affirming the Consequent
    ... >> argument undermining the claim that ID is real science. ... >> Intelligent Design: Affirming the Consequent ... >> The logical fallacy of affirming the consequent is explained as ...
    (talk.origins)
  • Re: Intelligent Design: Affirming the Consequent
    ... > argument undermining the claim that ID is real science. ... > Intelligent Design: Affirming the Consequent ... > The logical fallacy of affirming the consequent is explained as ...
    (talk.origins)
  • Re: Intelligent Design: Affirming the Consequent
    ... >>>argument undermining the claim that ID is real science. ... >>>The logical fallacy of affirming the consequent is explained as ... >>>about the designer they infer. ...
    (talk.origins)
  • Re: Commentary: The Worst Argument Against Intelligent Design
    ... my candidate for the very worst: "Intelligent design is not science ... The best is the observation that ID is simply the fallacy of Argument ... from Personal Incredulity. ...
    (talk.origins)
  • Re: Definition of ID?
    ... You may find it useful to distinguish between "intelligent design", ... came on board with their BTWBS pretense at science. ... With the crushing defeat of the creation "science" movement, ... Discovery Institute, and the Center for Science and Culture remains the ...
    (talk.origins)