Monday, October 12, 2009

Thinking clearly (part 2 of who knows how many)

Last week I opened up a discussion topic on logical fallacies, and I introduced a list of common fallacies that we run into frequently. The first one I listed was the "red herring" argument.

In my last post on this subject, I defined the red herring argument as "an argument that looks good, but is actually irrelevant to the content of the discussion." Wikipedia goes farther to say that a red herring argument is a deliberate attempt to digress from the content of the discussion. This is more devious than an innocent, irrelevant response to an argument, although I am not sure if the term "red herring" these days must refer to something deliberate.

A good example of a red herring argument is the "selection effect" in regards to the anthropic principle, which I have discussed in earlier posts. Here is the low down:

Greg: "The universe appears to have a very high degree of design (fine-tuning for the benefit of life), which would be very unlikely to happen by random chance. Therefore, it seems reasonable to conclude that God created this universe with a purpose."

Response: "Well, no, of course this universe appears designed. If it weren't so finely-tuned, we wouldn't even be here to observe it!"

Using an outline of our logic, we can easily see why the response is irrelevant:
  • Premise: This universe would never happen by strictly naturalistic means.
  • Conclusion: God created the universe.
  • Rebuttal: We wouldn't be here if the universe didn't happen the way it did.
What does that rebuttal have to do with answering the argument about the existence of God? (The correct answer is "nothing".) The selection effect, stated in this way, is irrelevant to this question. (There may be more sophisticated versions of the selection argument, but this serves well as an example.)