Wednesday, June 4, 2008

On Hume and a raging tiger

My belief that behind the purple door there is a raging tiger who would painfully kill me in a way that is very bad for me is sufficient to motivate me not to open the door. According to Hume, one needs to add to this belief the desire not to be painfully killed. Adding such a desire on top of the belief seems quite unnecessary.

What, then, do I make of the apparent possibility of Simone's believing that behind the purple door there is a raging tiger who would painfully kill her in a way that is very bad for her, and yet her being entirely unmoved by this belief? It seems that this possibility implies that there must be something more than the mere belief that is motivating me, since Simone has the belief and is not motivated. But this reasoning is fallacious. That there are cases where an A-type event does not cause a B-type event does not imply that something more than an A-type event is needed to cause a B-type event. It could, instead, be that there is something more in the cases where the A-type event does not cause a B-type event, for instance some defect that blocks the AB causal pathway.

What explains that Sally the Sheep is four-legged is just her being a sheep. Her mate, Rob the Ram, is three-legged, although he is just as much a sheep. We do not need to posit a further cause of Sally's four-leggedness beside her being a sheep. Rather, we need to posit a further cause of Ram's three-leggedness, such as genetic damage or an accident with some equipment in his woodworking shop.

Typically, when A-type events normally cause B-type events, a sufficient explanation of a B-type event in normal circumstances need only cite an A-type event. But when there is a departure from the normal, something more needs to be cited. Now it is clear that my being motivated by my belief is the norm, while Simone's case is abnormal. Thus, rather, it is Simone's case that calls for a further explanation, not mine.


Anonymous said...

Every time you talk about Hume I have no idea what you are talking about.

Do you mean you have an aversion to the tiger?

Hume is saying that you believe there is a tiger behind the door, you have an aversion to opening the door, so you don't.

If you can stand in front of a door with a ferocious tiger, and not have an aversion to opening the door, then you are not typical.

You can pretend that you make decisions dispassionately like that, but you are just not imagining the actual situation. If we put you in front of such a door, and we monitored your heart rate and pulse etc., I am confident we could show your aversion, beyond your pretended rational decision to open the door.

Tim Lacy said...

I suppose that we could justify Hume's addition if we talk about suicide. This is an exceptional-but-not-unheard-of circumstance, and it points to a contrary situation.

Being suicidal, Simone knows the outcome is bad, but wants it anyway. Her ~desire~ to end her life would overcome the force of reason behind her ~belief/knowledge~ of the consequences of opening the purple door. - TL

Anonymous said...

"Her ~desire~ to end her life would overcome the force of reason behind her ~belief/knowledge~ of the consequences of opening the purple door."

That's now how Hume looks at it. It would be her desire to die would overcome her aversion to the tiger. Only a passion can counter a passion, reason cannot do that. That is Hume's whole point. See Book 2 of the Treatise.

was it something I said...

What motivates you not to open the door is your belief plus your desire. What ordinarily explains your inaction is your belief, since your desire goes without saying. But it is still there, as part of your motive.

Similarly with the sheep. What explains Sally having 4 legs is her being an ordinary sheep, not just a sheep.

Were your belief sufficient to motivate your inaction, then were your desire different you would still be inactive. Maybe that is so for you, but for some people that will be false, and not because of some weird desire that they actually have.

Alexander R Pruss said...


I am, of course, denying Hume's idea that I need an aversion to death for the belief to motivate me. It seems clear to me that the stated belief is sufficient to motivate action. Now it is no doubt true that in the actual situation, there would be passion (except in exceptional circumstances, such as when one is too exhausted). But what I question is whether the passion is needed to motivate the action--the belief seems quite sufficient, and I see no reason to posit the passion as a necessary condition for the action.

I should add that it seems clear that beliefs are sufficient to motivate mental actions. Because of my belief that p, and my belief that q, I think that p-and-q. I don't need some kind of a passion to motivate me to think that p-and-q. But there is no reason to posit a significant difference between mental and physical actions (and if physicalism is true, then making the distinction is just about impossible).


In regard to Sally, I deny that what does the explaining is the claim that Sally is an ordinary sheep. For one, this threatens circularity, since a part of what makes Sally an ordinary sheep is that Sally has four legs. See also what I write about ceteris paribus laws and the van Inwagen objection in my PSR book, as well as what I say about the explanation of planetary orbits in Section of my "Leibnizian cosmological arguments".

Alexander R Pruss said...

I should say that I think the strongest counterexample to Hume is not this one, but one I heard from someone else. If someone asks me what time it is, I answer if I can. Why do I answer? Because I was asked. No further reason is needed.

WSIS said...

Yeah, you're right about the sheep. But it seems natural to say that desire motivates action, at least as natural as saying that belief motivates it.

Regarding being asked the time, I wonder if quite normal children might begin by looking blankly. When they are a little older they might respond with the time (when possible) only because they have just learned how to tell the time and want to show off.

A bit older, and they say "time you got a watch" or some such, and even later they pretend (if they can get away with it) that they did not hear you, just in case of various dangers; or maybe they respond as you would, being more sociable.

But the young child showing off and the adult being sociable, they both reply with the time (if they can) because they were asked, and yet there is a further reason that explains (more about) why.

Typed, not said...

Why does Sally have four legs? Because she is a sheep and sheep evolved from reptiles, which evolved from amphibians, which started out (as they stopped being fishes) with four legs (originally specialised fins); and because during that evolutionary process there was insufficient pressure to have other than four legs. It is a different story for snakes and bats etc.

So the reason why Sally has four legs might be an account of why sheep, unlike bats, have four legs. And had Sally been part of a flock that had been frequently attacked by a leg-chopping maniac, we would have added some reason why she in particular does not have fewer than four legs, e.g. she got lucky.

In general, the answer surely depends on why the question was asked (and thence on other things). Why does Sally have four legs (instead of two legs and two wings)? The answer "Because she's a sheep" is like replying to a question about what time it is with "Now."

Why does Sally (still) have (all) four legs? Because unlike spiders, sheep tend not to lose their legs. That answer could be a good one in some contexts, e.g. if the question was asked by a child who clearly knew that Sally was a sheep and that sheep have four legs, and who had just been asking about a six-legged spider.

And every question is asked in a context.

Kyle said...

Does this mean that you do not think that Plantinga's Evolutionary Argument Against Naturalism is sucessful?

Would you say that our believing correctly and acting accordingly is a simpler explanation than believing incorrectly and acting correctly due to some unusual desire?

WISI, not WSIS said...

Why did Sally have four legs?

Because she did not open the purple door!

Alexander R Pruss said...


If I'm right, then the desire-belief version of Plantinga's argument should be dropped.

But one can adapt Plantinga's argument. Instead of positing some weird background desire, one just posits odd wiring between the beliefs.

That said, I am sympathetic to the objection you give: I think odd wiring is a less probable evolutionary hypothesis.

I've had some go-arounds with Al on this by email. I think our deepest difference is in what we think the best naturalistic theory of mind is. I think the best naturalistic theories of mind are strongly externalistic in such a way as to make his argument fail. Al doesn't think these are the best naturalistic theories of mind. It's kind of an ironic disagreement, given that neither of us is a naturalist. :-)

Anonymous said...

"But what I question is whether the passion is needed to motivate the action--the belief seems quite sufficient, and I see no reason to posit the passion as a necessary condition for the action."

That's well and good, but you're not engaging Hume on his terms. You are not showing why Hume is incorrect, you are just offering an alternate explanation of how people behave, using a completely different notion of "belief" and "passion" from Hume.

Hume says that our passions motivate our behavior. He has a worked-out theory of this, which easily accounts for your whats-the-time-example. This may or may not be an accurate description of how people behave, but your examples don't show anything wrong with Hume's explanation.

Maybe you think your model of human behavior is more convincing than Hume's, but I think that most people who read the Treatise carefully will find some profound insights into the nature of belief and human action that cannot be so easily dismissed.

Alexander R Pruss said...

1. In what way do my and Hume's sense of passion and belief differ?

2. It is true that Hume can give an account of these cases. But the account feels forced in these cases.

3. The strongest argument I know for Hume's position is the imaginability of a case where one has a belief but is unmoved. And this argument I try to refute.

Anonymous said...

"1. In what way do my and Hume's sense of passion and belief differ?"

You talk about "adding on" passions to beliefs. First of all, beliefs and passions are interacting all the time, passions can increase the intensity of belief, and vice versa.

As far as I can tell, you have a model of dispassionate belief based on reason leading to action. Hume's saying something completely different. It's not an issue of what you can imagine, it's an empirical question of how people actually behave and how their motivations work. He is making a psychological claim, not a philosophical one. Even if you can imagine a being who behaves as you describe, even if you believe yourself to be behaving as you describe, Hume is claiming that people (you) *don't* behave in that manner.

"2. It is true that Hume can give an account of these cases. But the account feels forced in these cases."

Just to take the time-telling example, Hume would say that you feel sympathy for the guy asking the question and so you tell him. I don't see how that feels forced, that sounds like a good explanation to me. He would also have something to say about social convention, etc. He has a lot to say about that as well.

Alexander R Pruss said...

It's not so much that I have a model of dispassionate belief (on my preferred view, passions are very much belief-like), as that I see the motivation as, at least sometimes, coming from the conceptual content, rather than any passional component.

I don't think we need to feel anything for the person who asks what time it is. We just answer, because we were asked.

Alexander R Pruss said...

I should say that I am only worried about people who think that beliefs could not by themselves move us. If Hume only claims that as a matter of empirical fact they do not by themselves move us, then I don't really care about refuting Hume here. I am not Hume scholar--I care more about arguing against a particular view, than whether Hume actually held it, and I am happy to be corrected about Hume.

Anonymous said...

Well, Hume says that reason cannot/does not move us, but belief is not based on reason to begin with.

To quote the Stanford encyclopedia quoting Hume:

Belief is thus “more an act of the sensitive, than of the cogitative part of our natures” (T, 183), so that “all probable reasoning is nothing but a species of sensation”

Beancan Tatterpants said...

"If someone asks me what time it is, I answer if I can. Why do I answer? Because I was asked. No further reason is needed."

This example leads to meaninglessness. Let's say someone asks me what time it is, I refuse to answer despite being able to. Why don't I answer? Because I was asked. No further reason is needed.

Having both outcomes from the same premise makes the action arbitrary and requires more reasoning. You might say that the person not giving the time is acting out of the social norm and thus, needs more explanation to the action beyond just being asked.

But that, to me, necessitates both 1) being asked and 2) adhering to a set of social mores that require you to answer when asked the time (if possible).

If the premise were all that was needed, then any response would be justified by it. Why did I punch that man? He asked me the time. Why did I scream Mercutio's monologue at him? He asked me the time.

Clearly more reason than "I was asked" is needed to explain the resulting behavior.

Alexander R Pruss said...

That someone asks me to do something is by itself a reason to do it. Doing something I have a reason to do does not call for further explanation. Failing to do something I have reason to do does call for a further explanation.