Today we're going to be talking about two additional fallacies of relevance.
One of them is what we'll call appeal to popular opinion.
It's related to some versions to appeal to authority.
The other is unlike all the other fallacies of relevance that we've looked
at because Speaker: It's not a deductive fallacy, it's a practical fallacy.
It's a fallacy in practical reasoning. In order to see what these two fallacies
are, let's begin by looking at the following clip in which both of them
occur. Speaker: You know if we don't catch that
fish, we both know there ain't going to be any deep sea fishing.
We'll have to stay on the dock like the old people.
Hold it, hold it, what are you doing here? Speaker: What? Speaker: What about
the other foot? There ain't no sock on it.
Speaker: I'll get to it. Speaker: Don't you know that the whole
world puts on a sock and a sock, and a shoe and a shoe? [LAUGH].
I like to take care of it one foot at a time.
[LAUGH]. Speaker: That's the dumbest thing I ever
heard in my life. [LAUGH] Speaker: It's just as quick my
way. Speaker: Wait a minute, that aint the
point. You see what I'm talk, don't keep doing
it. Listen to me.
[LAUGH] Suppose there's a fire in the house and you gotta run for your life.
[LAUGH] Your way, all you got on is one shoe and a sock.
[LAUGH] My way, you got on a sock and a sock. You see, they're even.
[LAUGH] Suppose it's raining or snowing outside, your way with a sock on each
foot, my feet would get wet. My way with a sock and a shoe on one
foot, I could hop around and stay dry. Speaker: I think you've been hopping
around on your head. Speaker: [LAUGH].
Speaker: Wait, wait and, listen to me. Speaker: [LAUGH].
Speaker: Suppose then the other socks got a hole in it.
Speaker: [LAUGH]. Speaker: It doesn't have a hole in it.
Speaker: I said suppose that it's got a hole.
Speaker: Alright suppose it has a hole. Speaker: Alright it's got a hole in it,
so Speaker:You ain't got another matching pair, so what are you going to do? Your
way, you gotta take off a whole shoe and a sock [LAUGH] My way, all you gotta do
is take off one sock [LAUGH] Speaker: All right, if it'll make you happy I'll start
all over again. Speaker: No, no, no [LAUGH] You're
halfway through Oh, gee get on with it, we're in a hurry.
[LAUGH] You can start doing it the right way tomorrow morning.
Speaker: Older American students might recognize the clip that we just saw as a
clip from the TV sitcom, All in the Family, which ran in the United States in
the 1970s. In it, the older character with white
hair is named Archie, and the younger character with brown hair and a mustache
is named Michael. In the clip we just saw, Archie gives
Michael 3 arguments, and each time Archie gives Michael an
argument, that argument commits a fallacy of relevance and Michael attempts to
rebut or respond to the argument. Let's consider the first argument that
Archie gives Michael. When Archie sees Michael putting on a
sock and a shoe and then proceeding to put on another sock, Archie says Don't
you know that the whole world puts on a sock in a sock and a shoe in a shoe? The
implication being, that since the whole world puts on a sock in a sock and a shoe
in a shoe, Michael should also. So, Archie is implicitly giving Michael
the following argument. Premise, the whole world puts on a sock
and a sock and a shoe and a shoe. So conclusion, you ought to put on a sock
and a sock and a shoe and a shoe, and since you're not doing that, you're doing
it wrong. That's the first argument that Archie
gives Michael. Now notice this argument is guilty of a
fallacy of relevance that's very similar to the fallacy committed by some versions
of appeal to authority. Even if it's true, and let's grant for a
moment that it is true that the whole world puts on a sock and a sock and a
shoe and a shoe. That doesn't mean that you ought to do it
that way as well. Now maybe there's a good reason why the
whole world puts on a sock and a sock and a shoe and a shoe, but if there is a good
reason why the whole world puts on a sock and a sock and a shoe and a shoe, then
that good reason is the good reason why you ought to put on a sock and a sock and
a shoe and a shoe. In other words, it's not that the whole
world puts on a sock and a sock and a shoe and a shoe, that explains why you
want to put on a sock and a sock and a shoe and a shoe.
Rather, if there's a good reason why other people put on a sock and a sock and
a shoe and a shoe, then that very same reason is the reason for you to put on a
sock and a sock and a shoe and a shoe. So, this argument right here is no good
even if its conclusion is true, because there's some good reason for the premise
being true. This is an example of appeal to popular
opinion, or we can say popular practice. Sometimes popular practice is a good
guide to what we ought to do. But sometimes it isn't.
So, is popular practice in this case, a good guy, to what we ought to do? Only if
there's a reason why it's the popular practice only if there's a good reason
why everyone puts on a sock, and a sock and a shoe in a shoe.
Michael obviously doesn't think there's a good reason for everyone to put on a sock
and a sock and a shoe and a shoe. So, the fact that the whole world does
so, assuming it is a fact, is irrelevant to him, and he says he likes to take care
of one foot at a time. So, simply because everyone else does it
differently He thinks, there's no reason why he should do it the way they do.
He's happy to take care of one foot at a time, and until Archie can give him a
good reason for doing what the whole rest of the world does, Michael's going to
take care of one foot at a time. Okay.
Now, let's consider whether Archie can give him a different reason.
A good reason. for putting on a sock and a sock and a
shoe and a shoe. Next, Archie tries to give Michael
another argument for why he should put on a sock and a sock and a shoe and a shoe.
Archie's next argument goes like this. Well, suppose you have to leave the house
halfway into putting on your footwear You don't get to put on all your footwear,
you have to leave halfway. Let's say there's a fire and you have to
run out of the house. Now if you put on both your socks first.
In other words if you're putting on a sock and a sock and then a shoe and a
shoe, then when you have to rush out of the house.
Half way through putting on your footwear, your feet won't be even.
You'll have one sock on each foot. But, if you would have been putting on a
sock and a shoe, and a sock and a shoe, then when you have to rush out the house
halfway through putting on your footwear, your feet will not be even.
You'll have a sock and a shoe on one foot and the other foot will be bare.
Now, i'ts better for your feet to be even than not.
Archie doesn't explicitly say that, but clearly he implies it.
Since it's better for your feet to be even than not, It's better for you to put
on both your socks first, in other words, it's better for you to put on a sock and
a sock and a shoe and a shoe. Better to do that than to put on a sock
and a shoe and a sock and a shoe the way Michael's doing it in the video.
So, is this a good argument for why it's better to put on.
A sock in a sock, and a shoe in a shoe? No it's not.
And what Michael says in response to Archie, tells us something about why this
is not a good argument. See the reason this is not a good
argument is because it starts off by supposing a scenario that's very unlikely
to happen. It's very unlikely that halfway into
putting on your footwear, you'll have to evacuate the house because of a fire.
Now, of course sometimes it's good for us to take precautions against scenarios
that are very unlikely. For instance, you might buy health
insurance to pay for an, any expenses that you incur in case of some
catastrophic illness, or flood insurance, to pay for the
damages that'll occur to your house in case of some catastrophic flood.
Even though it's unlikely that you'll become catastrophically sick, or you'll,
your house will undergo some catastrophic flooding.
Still, the reason it makes sense for us to take precautions against those
scenarios is that, even though those scenarios are unlikely, if they were to
happen, the consequences of not taking precautions would be really, really dire.
Right, getting catastrophically sick without having any means to pay for your.
Treatment would be a terrible thing and having your house destroyed without any
means to recover the loss of it would, again be a terrible thing.
So even though those scenarios are unlikely, it still makes sense for us to
take precautions against their happening because if they did happen that would be
terrible. But how terrible would it be for your
feet to not be even, for you to have a sock and shoe and, on
one foot, and the other foot bare? Well, it wouldn't be so bad.
Certainly not as bad as your housing burning down.
So, what Archie is doing is he's appealing to a scenario that's very
unlikely to happen, and then he's showing that if you put on
a sock and a shoe and a sock and a shoe, the costs that you would incur in that
scenario, while they exist, are not all that substantial.
The costs would just be that your feet would not be even.
So Archie is trying to argue that it's better to put on both your socks 1st, by
appeal to a scenario that's 1st very unlikely to happen and secondly even if
it did happen the costs to you of putting on a sock and a shoe and a sock and a
shoe wouldn't be all that great. So that's why this is not a good
argument. And what Michael does in response to
Archie's argument, is to show that a perfectly analogous argument could be
given in favor of the opposite policy of putting on a sock and a shoe, and a sock
and a shoe. Michael says, well look, suppose, suppose
you're right Archie, that you do need to evacuate your house half way into putting
your footwear on. But suppose also that it's raining
outside. Might as well be raining outside.
That's, that's not significantly less likely than your having to evacuate when
it's not raining outside. So suppose it's raining outside [SOUND]
and you have to evacuate your house [SOUND] halfway into putting on your
footwear. Well, if you ave a sock in a shoe on one
foot, then you can hop around and stay dry.
But if you only have a sock and a sock on each foot, then you're going to get wet.
Once again, Michael shows that this same kind of argument appeal to an unlikely
scenario, and appeal to some. Miniscule cost associated with the
obtaining of that scenario. That very same argument could be used to
favor his way of putting on his socks and shoes as it can be used to favor R.G.s
way of putting on his socks and shoes, right? So,since that very same kind of
argument can be used for either conclusion.
It's not a very compelling argument. Either way.
Appealing to an unlikely scenario which if it were to obtain would carry with it
some minuscule cost, is not a way to show that one course of action is better than
another course of action. In this third argument, Archie corrects
the defects that I just pointed out, in the second argument.
First he appeals to a scenario. That's much more likely to occur than the
scenario of your having to evacuate the house immediately, halfway into putting
on your footwear. And secondly, he appeals to a cost that's
a little more substantial than the cost of your feet not being even.
Let me explain what I mean. Archie asks Michael to suppose.
That Michael finds a hole in his second sock, as he's putting his second sock on
his foot. Now, that's not an impossible scenario.
It's probably, more likely to occur than having to evacuate the house.
Half way into putting on your footwear. But suppose you find a hole in your
second sock while you're putting it on your foot.
Well, if you were putting on a sock and a sock and then a shoe and a shoe, finding
a hole in your second sock Would be easy to correct.
You'd just take off your socks. Put on another pair of socks without a
hole in them. And then put on your shoes.
But, if you were doing things Michael's way, and putting on a sock and a shoe,
and a sock and a shoe. Then, you'd have to take off the shoe
that you already put on your first foot. If you found a hole in the sock that's on
your second foot. Since it's easier to remove socks than it
is to remove shoes, let's suppose, Archie concludes it's better to put on a sock
and a sock and a shoe and a shoe than to do it Michael's way and put on a sock and
a shoe and a sock and a shoe. And again the reason it's better is
because In this scenario, where you find a hole in your second sock, it's easier
to fix it if you would put your socks on before putting your shoes on.
So it's easier to fix a problem that crops up in this scenario if you're
putting on a sock and a sock and a shoe and a shoe than it is to fix that same
problem If you are putting on a sock and a shoe and a sock and a shoe.
Now this argument appeals to a scenario that is a lot more likely to happen, I'm
supposing than the the scenario of having to evacuate your house halfway into
putting on your footwear and it also appeals to a cost that is perhaps a bit
more substantial, a bit more obvious. Than the cost of having your feet,
unbalanced having your feet not be even. But, while Michael accepts this argument,
Michael doesn't rebut this argument, it's not clear how compelling the argument is.
How would we judge the compellingness of this argument? How can we tell If this is
a good argument or not. [SOUND] Well, here's what we have to do.
[SOUND] Think back to Walter's discussion of practical reasoning.
[SOUND] Let's say you're deciding between two different courses of action.
[SOUND]. One course of action is putting on socks
first and the other course of action is one foot at a time.
[SOUND] So those are your two choices. Are you going to put on your socks first
and then your shoes, or are you going to put on your footwear
one foot at a time? Well, these courses of action are
going to have different outcomes, depending on The way the world is, right?
There are different ways the world could begin, depending on the way the world is.
These courses of action will turn out differently for you.
So suppose for instance, you have to evacuate your house.
Halfway into putting on your footwear. That's one possible way the world could
be, and under that scenario you'd be a little bit worse off going one foot at a
time, then you would with socks first. At least if it's true that it's a bad
thing to have your feet be unbalanced. But there are many other ways the world
could be. Now, in order to figure out which of
these two policies is the better one, which of these two courses of action is
the beter one, what we need to do is to consider all the different ways that the
world could be. And then, consider what the costs and
benefits of these policies would be under each of those scenarios.
So let's say that we have five possible scenarios, scenario 1 One two three four
five. And under scenario one, your'e a little
better off putting on your socks first than going one foot at a tlme.
Alright, so let's say putting on your socks first, that's a really good thing,
wheras going one foot at a time. It's okay, but not great.
'Kay, under scenario two let's say putting on your socks first turns out
really badly. But putting on your footware one foot at
a time again turns out okay. And so on.
Now, suppose we discovered that no matter what happens, putting your footwear on 1
foot at a time turns out Okay, whereas putting on your socks 1st turns out
really well under some scenarios but really badly under other scenarios.
Then what should we do? It depends and in particular it depends on how likely these
different scenarios are to a curve, how probable they are to a curve.
If scenario 1 under which putting on your socks 1st turns out really well, if
scenario 1 is really likely to occur, let's say there's a 90% chance that
scenario 1 will occur and scenario 1 it turns out really well if you put on your
socks 1st. But not so well if you put on your foot
wear one foot at a time. Well then that's a pretty powerful reason
to put on a sock and a sock and a shoe and a shoe.
On the other hand, if, under one of these scenarios, let's say putting on your
socks first, results In your death, then that's a really powerful reason not to
put on your socks first. Because if putting on your socks first
could even with a 1% chance result in your death, it's probably not worth it.
Probably better to put on your footwear on one foot at a time.
So, if we're trying to figure out if Archie's third argument, compelling or
not, what we need to figure out is this. How likely is it, that you're going to
find a hole in your second sock? And. If you do find a hole in your second
sock, how much worse is it to have to remove your shoe versus removing your
socks. And finally what are the other possible
outcomes Of putting on a sock and a sock, and a shoe and a shoe.
Versus putting on a sock and a shoe, and sock and a shoe.
We have to consider all of the possible outcomes.
Because, if there's some outcome that has even a 1% chance of happening.
Where the consequences of putting on a sock and a sock and a shoe and a shoe are
catastrophic, like let's say you die,
then that's a pretty good reason in favor of doing things the other way.
Because the advantages to the gain from putting on a sock in a sock and a shoe in
a shoe probably are not great enough to compensate for the risk of death, that
you would undertake if this scenario was even 1% likely.