Monday, February 23, 2009

Logical Fallacies and Creationists

I've noticed that many creationists seem to be susceptible to logical fallacies. Let's look at two examples:

The fallacy of division is to attribute to individual parts something that is characteristic of a whole. For example, water is wet, so individual atoms of water must be wet, too.

A particularly nice example of this fallacy was recently posted by someone named "Gizmo" commenting on a ridiculous article by British columnist Christopher Booker:


A good illustration of the existence of God is provided by all these wonderful arguments & counter-arguments!

If only people could see that cells & DNA cannot hold an idea or opinion, and cannot have a debate.

We are far more than just flesh & blood!


Gizmo's "reasoning" seems to be

1. People hold ideas and opinions.

2. Suppose that people consist solely of "cells & DNA".

3. Then "cells & DNA" hold ideas and opinions (by the fallacy of division).

4. But "cells & DNA" cannot hold ideas or opinions.

5. Therefore there must exist something in people besides "cells & DNA".

Another logical fallacy popular among creationists is the continuum fallacy. In this fallacy, the writer tries to get a contradiction by positing the absurdity of obtaining a property incrementally. It is sometimes called the fallacy of the heap, because it is illustrated by the following: one grain of sand doesn't form a heap. If a pile of sand is not a heap, then adding a single grain can't make it a heap. Therefore two grains of sand don't form heap, and neither do three, four, etc.

Here is a nice example from the writing of ID's intellectual leader, William Dembski:


Out pop purpose, intelligence, and design from a process that started with no purpose, intelligence, or design. This is magic.


What Dembski fails to grasp is that "purpose", "intelligence", and "design" are not necessarily black-and-white properties. People can be said to be intelligent, but why not chimps? Why not their common ancestor? Why not the ancestor of that creature? Etc. Intelligence is a continuum, and there is no reason to believe it cannot arise slowly through evolution.

4 comments:

Anonymous said...

I'd pair up the fallacy of division with the fallacy of composition ("what's true of the parts is true of the whole") and notice that there are lots of creationist uses of it.

I've seen it used as part of the "second law of thermodynamics" argument. But then that's such a muddle of fallacies that it may be persnickety to pick out any one.

But most common seems to me is the confusion among creationists between the origin of species and either (fallacy of division) origin of individuals or (fallacy of composition) origin of life/universe.

Tom S.

Barry said...

The property of "intelligence" also depends on who is doing the evaluating.
My cats frequently do not think I'm very intelligent. About a hour and a half before dinner time they think I'm dumb as a post.
They may be right.

Takis Konstantopoulos said...

I think that, according to Gizmo and the creationist logic you clearly exemplified, the argument about water ought to go like this:

* Water is wet.
* Individual atoms of water are not wet.
* Therefore, there is more to water than just individual atoms.
* Hence water has a soul.

Oh, the miracle of creation! Even water shows the existence of intelligent design!

By the way, the Daily Telegraph is not a very good newspaper. So it's not surprising that it hosted the ridiculous article by Booker.

B M McManus said...

I think that if creationists were forced to learn about the concept of emergent properties--I mean really understand it--there would be far fewer creationists.