Saturday, October 07, 2006

Parallels

Josh writes:

Here's an argument:

There is an obvious difference between a fertilized egg and a baby. Nevertheless, as there is no clear line at which life (and with it the right to life) begins, the morally safest thing to do would be to act as if life begins at conception, and outlaw abortion.

Here's another argument:

There is an obvious difference between a smack on the bottom and a sustained beating. Nevertheless, as there is no clear line at which harmless discipline becomes harmful child abuse, the morally safest thing to do would be to act as if it's all harmful, and outlaw smacking.

Spot the difference.

15 comments:

phats said...

A few years ago when I was still pro-life, I would have said you're misrepresenting argument one.

People making argument one would often have a supressed premise that "Aside from survival of the Human Species, individual right to life is the supreme moral imperative and therefore trumps all non life-related concerns.

An equivalent of that premise is not present in argument two.

These days -now that I am trying to play Doctor- I realise that over half of human embryos are spontaneously aborted, so I think God should fix his own damned system if he is so concerned about it.
I don't see the pro-lifers researching drugs to reduce this spontaneous abortion rate, do I?

Josh said...

When you say "misrepresenting argument one", I assume you mean "misrepresenting the views of the sort of people who would likely espouse argument one, i.e. pro-lifers". Could be -- usually when I hear a variant of that argument, it's used to "prove" that life begins at conception, rather than suggesteding the adoption of the "act as if" attitude.

If anthing though, I thought I was misrepresenting the second one, since the sort of people who'd adovcate for that position go to lengths to point out that they're not about outlawing smacking; they're about making adults and children equal under the law or some such.

I don't see that your suppressed premise is necessary for argument one, though a similar one could be introduced for argument two, given that in extreme cases child abuse can lead to death.

At any rate, that was more an exercise for my philosophical muscles, pointing out that the exact same argument form is likely to be accepted in one situation and not in the other, making both conservatives/right-wingers/pick your stereotype just as inconsistent as liberals/left-wingers/pick your other stereotype.

The Hand of Morthos said...

Hold your horses, Josh; just because the argument structure is the same doesn't mean the arguments are in any way equivalent, otherwise we'd be having the same debate about the following examples:

Socrates is a man
All men are manitcores
Therefore, Socrates is a Manticore

and the equivalently structured argument

Socrates is a man
All men are mortal
Therefore, Socrates is a Mortal.

Premise plausibility is the next important step, and premise one of the second argument is, arguably (and here we get into a whole definitional problem about things such as abuse and violence), implausible. Indeed, with the material task taken into consideration the second argument is structurally different to the first; the first premise of argument two can be argued to be irrelevant (as support for the conclusion) whilst the first premise of argument one probably is relevant.

Josh said...

I didn't say the arguments were equivalent, I said the forms were. Both rely on the (fallacious) "slippery slope" assertion that because there is no clear point at which A becomes B, it was B all along. (Or, as I put it in an attempt to make the arguments less powerful but more persuasive, we should act as if it was B all along.)

As a matter of emprirical fact, this assertion is considered convincing by people making the first argument (we've both seen it made many times), but I would place money on them finding the same assertion ridiculous in the case of the second.

The Hand of Morthos said...

I suppose I may have inferred too much from:

'At any rate, that was more an exercise for my philosophical muscles, pointing out that the exact same argument form is likely to be accepted in one situation and not in the other, making both conservatives/right-wingers/pick your stereotype just as inconsistent as liberals/left-wingers/pick your other stereotype.'

but it did sound as if you were saying that the arguments were equivalent. Of course, you're right that slippery slopes get different treatments based upon their premises but that's because not all slippery slope arguments are fallacious (indeed, that there are lots of legitimate slippery slope arguments is one reason why the fallacious ones are so pyschologically persuasive).

Josh said...

I can't think of a valid argument like this - can you give an example or two?

The Hand of Morthos said...

All chain arguments are valid; if A then B, if B then C, if C then D, therefore if A then D; that's the logical form of the slippery slope (aka hypothetical syllogism). It's usually the premise plausibility where such arguments fail (i.e. soundness). Hmm, examples:

Illegitimate Slippery Slope example:

If you walk to University in the morning you will have to walk to Queen St. If you are on Queen St then you will need to cross the road at a major intersection. If you cross the road at a major intersection you are likely to be run over by one of Auckland’s many bad drivers. So you shouldn’t walk to University in the mornings.

Legitimate slippery slope example:

If you buy one of those 4-wheel drive monstrosities, then you will have to enlarge your existing Ponsonby Villa's garage. If you want to enlarge your garage, then you will have to knock out the wall dividing the garage and the bathroom, and make the bathroom smaller. If you make the bathroom smaller, you’ll find it very hard to sell your house. So you shouldn’t buy one of those 4-wheel drive vehicles.

(This one has some built in assumptions based upon the context under which it is uttered, but most arguments in ordinary language are like that)

A debateable example:

P1. If the government survives a full three-year term, then taxes will remain stable.
P2. If taxes remain stable, small businesses will suffer.
Therefore,
C. If the government survives a full three-year term, small businesses will suffer. (From P1 & P2)
P3. We don’t want small businesses to suffer.
[P4. We do not want something to happen if it will lead to a bad outcome.
Therefore,
C2. We don’t want the present Government to win the next election (from C1 and P3).

My favourite fallacious example:

The Roman Catholic Church must condemn all computational devices, even calculators. Why? If we allow computational devices to exist then such devices will become more advanced and more capable, as we have seen with the advent of the home computer. Eventually such devices will become as complex and advanced as the human brain, and if they do that then they will, eventually, be able to function like a human brain and have the capacity of thought. If we have thinking machines then eventually we will consider such machines to be like us, and we will grant them the same rights and privileges as ourselves. If we do this then eventually some of these machines will join the Catholic Church. If they join the Catholic Church then eventually some of them will become priests, and then bishops and eventually they could become Pope. If we have a machine as Pope we will have a Pope who need not ever die, and we can't have an ever-living Pope, can we?

Josh said...

Ah, I should've been more clear. I'm not talking about what are commonly called slippery slope arguments/chain arguments - I'm talking about the from that in the context of anti-abortion arguments (which is where it's chiefly used) gets called the "slippery slope argument" (at least it did when I studied it in Applied Ethics). I always thought that was a bloody stupid name for it, for exactly this reason - people hear "slippery slope" and think of another sort of argument entirely (or think of something rude, but let's not bring Richard into this).

Are there any valid arguments involving the claim that because the gradual progression from A to B offers no clear point at which A becomes B, B was the case from the start?

Josh said...

Oh, and I agree that your Catholic example is completely unsound - I personally long for the day when we make a robot Pope. Mechapope shall rule us all with his death beams and mighty pistions of righteousness!

The Hand of Morthos said...

Usually those arguments fall down because the, for lack of a better term, the definition/distinction premise is usually implausible (or, at least, open for debate). The foetus/baby example is a good one; that definition is being continually challenged (recent medical evidence indictates that if we run the abortion line on when something becomes significantly human then we have to disallow abortions after about six weeks) and the smacking one runs on a version of Begging the Question as it builds into the argument a definition of violence/abuse. Actually, Begging the Question is probably where these arguments really turn fallacious; we state the distinction as being obvious when it really isn't and then trade on that when we come to infer the conclusion.

Josh said...

I think you could actually remove the fallacy from those arguments, provided what you want from them is a guide for how to act, rather than hard logical proof. For example:

Even if you believe that there is a clear difference between A and B, the fact that there's no clear point at which A becomes B etc etc... therefore, in order to be sure, we should act as if B were the case.

I actually find this fairly persuasive - in the case of abortion, if our primary concern is that we don't act unethically by killing what is actually an innocent human being, then, in the name of "better safe than sorry", we should assume that life begins at conception, even though that appears to be too soon to draw the line -- indeed, the very fact that it seems too soon to draw the line suggests that we are erring on the side of caution. But then I am a fallibilist...

Of course, because this line of reasoning doesn't provide concrete proof that abortion is just plain wrong, and because it assumes the primary concern I mentioned, there's plenty of room to argue the other way. But isn't there always?

The Hand of Morthos said...

Well, it's all an issue to do with the Burden of Proof (which is usually a fairly good guide as to what side of an argument you should support (as long as the evidence isn't clear)). It's actually the main reason why I find Climate Change Skeptics so bewilderingly unreasonable; even if we grant them that idea that the evidence isn't clear then they should still consider the burden of proof in this matter (which is to do with public safety).

phats said...

I have seen that four-wheel drive argument somewhere before... like in today's lecture..

(The up shot of going back to uni is you get to squeeze in a fun paper here and there)

The Hand of Morthos said...

Yes, well, Jon and I co-wrote most of PHIL105. You've probably already experienced some of my more exciting contributions like the Meredith's, the Corrins and, to my great shame, the gameshow pervert Chip, who I play loud and proud.

phats said...

I had thunk as much :)