Sunday, September 03, 2006

Logical fallacies

Maybe some of you can help me.

I've encountered--you probably have too--some debate tactics that are flawed but don't seem to have a formal name. I'm wondering if proper names do exist, and if not, I'd like to come up with some. I often find that challenging someone on an erroneous logical shortcut is more effective when you can show that someone has already dissected and labeled the error. It's not a logically consistent tactic, itself, but sometimes the appeal to authority is the only thing that works when someone's experienced other lapses in reason.

The first one I've been referring to as the "If it weren't for you" fallacy. Consider two parties disagreeing on some topic. With neither side able to persuade the other, one asserts that the other is at fault for starting or prolonging the argument, so it is guilty of simply being disruptive of or maliciously contrary to the other position (implied to be correct by the conceit of such an assertion), and thus does not deserve to be taken seriously: "We wouldn't even be having this argument if you just did what we wanted!"

The second hovers somewhere between begging the question and Pascal's Flaw. Begging the question--not raising the question--is where an argument makes an assumption in its proof that is not explicitly stated or itself justified.

Pascal's Flaw derives from Pascal's Wager, which states that given the risks and rewards of believing in God versus not believing in God, it would be most prudent to believe in God, whether or not He exists. The Flaw is the logical gaps in the proposition, such as the complete disregard for whether God exists after all, or the presumption that God would be the sort of entity that would reward worship and punish dissidence. It may not be begging the question so much as oversimplifying an argument; while not thoroughly rigorous, the God of Pascal's Wager is one he and his contemporaries would be most inclined to think of.

This second fallacy I've been calling "presumptuous caution." It masquerades as the honest caution one might use in tentatively settling an unresolved debate, such as "Building a new commercial district on the edge of town could revitalize the city, but we shouldn't commit ourselves unless we can determine that enough of our residents would be willing to drive that far to patronize the new businesses."

Presumptuous caution makes such an assertion prematurely, and uses a gap of knowledge or logic as positive evidence for one position rather than as a mitigating condition that can bring us to a decision when no formal resolution is imminent. The above example would take the form "Building a new commercial district on the edge of town could revitalize the city. We're not sure if enough residents would be willing to drive that far to patronize the new businesses. Therefore, the district should not be built at all."

1 comment:

beepbeepitsme said...

RE: logical fallacy

What Is Evidence?
http://beepbeepitsme.blogspot.com/2006/09/what-is-evidence_07.html