On Logic

Logic only shows us valid and invalid forms of argument. Too many people misuse the word 'logic' or treat it like some kind of magical weapon. I even hear statements that logic is the sole domain of atheists. Let me tell you something: logic is no one's slave.

Consider this argument:

God is love.
Love exists.
Therefore, God exists.

This is a completely logically valid argument. That is, the conclusion logically follows from the premises. But is it true? Is it sound? These are questions that logic cannot answer. Logic cannot tell us what the truth is. It can only tell us if an argument is valid. If we accept the premises as true, then we accept the conclusion as true. If not, then not. (If you didn't notice, I'd just formed a logically valid argument.)

Logic is a construct. As such it cannot stand alone. Logic is a lot like math. Math is meaningless on its own, but incredibly useful in the right context. Consider the following formula:

x = y+1
a * x = n

Now, that seems meaningless on its own. However, let x = the retail sales tax in the state of Kansas (i.e. about 7.52%, or 0.0752). Using the formula, y = 1.0752, which is the multiplier you'd use to discover the final cost of a product after tax. Let a = the initial cost of the product, and let n = the final cost (rounded to the nearest hundredth). If we want to buy a $1 candy bar, the actual cost would be $1.08.

0.0752+1 = 1.0752
1 * 1.0752 = 1.08 (rounded to the nearest hundredth)

Suddenly the formula is a lot more useful. But not by itself. It only becomes useful when values are introduced that we already consider valuable. It means nothing on its own. Math does not "belong" to anyone--it is only a tool to be used. Logic is exactly the same way.

In a forum I was recently posting in, someone posted a topic asking for a White History Month. When a regular poster told him to crawl back under the rock where he belonged, he demanded a "logical" response. So I gave him one.

1 Premise: You belong under a rock.
2 Premise: You crawl rather than walk.
3 Corollary: Were you to return to the rock where you belong, you would crawl to get there. (From 1 and 2)
4 Premise: Those who do not contribute to the forum should leave.
5 Premise: You do not contribute to the forum.
6 Conclusion: Crawl back under the rock where you belong.

I just proved, logically, that he should crawl back under the rock where he belongs. If you accept the premises, the conclusion follows. Perhaps the word he was looking for was "rational" rather than "logical." But then, why should anyone bother posting a rational response to such an irrational topic?

Let's try to recap, here. Logic is a method to determine the validity of an argument. That is, it helps us differentiate between valid and invalid forms of argument. Note that an argument's validity has nothing to do with its truth value. Consider the following argument:

People have gills.
Animals with gills can breathe underwater.
People can breathe underwater.

This argument is valid even though it is obviously untrue. The argument is not true because the first premise is not true. However, the conclusion follows from the premises, making it a valid argument.

Logic is not your badge of authority, so stop treating it like one.

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