David Hume said we cannot directly perceive causation, but that's not true. We experience causation all the time.
Just wiggle your finger.. (she wiggles it) Now, focus in on that control you feel while you do it. Got it? Now, make your heart skip a beat.
Hey, c'mon, that's different!
Yes, and that's precisely my point! You can cause one but you can't cause the other. That's the difference!
Hmm…that seems sketchy to me. (deep in thought) I got it! I can make it skip a beat. Move over.
What? Okay, I've got to see this. Don't hurt yourself.
Don't worry, I won't. (She lies down on her side, feeling her pulse) Yep. Feel it and weep.
(He feels her pulse) Holy shit, you did it! What's your trick? How do you do it?
I have conscious control over my heart.
Shut the fuck up.
No! It's true. I know that whenever I lay on my right side, my heart tends to skip. It's a correlation I can count on. That's all causation is—correlation you can count on.
Bullshit! Consciously doing something else that you know will affect your heart is clearly different from consciously controlling your heart directly.
How? How exactly is it different?
Well, it's hard to put into words.
I thought it was supposed to be clear…
It is, perfectly clear in fact. Something can be perfectly clear without being easy to put into words.
Well, um…like…like this! Like how it is totally clear how something can be totally clear but hard to put into words, but hard to put into words.
But listen, that's besides the point. The point is, you agree that when you lay down just then, you did it to speed up your heart.
But you can't speed up your heart without doing that.
Well, so far as I know right now…
Yeah, yeah good enough for me. So that's completely different from there being no other actions that you need to perform to make your heart skip other than the very act of skipping your heart.
Hmmm…good point. But now that I think of it, this is exactly the point I'm trying to make—there's always intervening actions…it's just that some we're so used to that we don't even notice them. Or there's no mechanism for noticing them, because they're so innate.
But you're always acting in some way, that's my point…you're always causing action!
No, you're not.
How are you not?!
Listen, have you heard of these studies, where they hook up a person's brain stem to an electrode, and using a little electric shock they make the person wiggle his finger. Funny thing is, the person thinks he chose to wiggle his finger! He even reports to the people, "Oh, yeah I just decided to wiggle my finger right then."
Whoa!! I'll have to check out that study, but if it's true then, damn!
Yeah, that's what I'm saying! So, what if we're making up the story all the time, whenever something moves? In fact, that's precisely what we're doing! Everything happens according to the laws of physics. They have all the equations they need to predict how everything interacts--it's just the initial conditions that are hard to put into the equation because things are complicated. But they know the laws of the universe, and they know that everything obeys them. So do you. It's just that you have this propensity to make up a coherent story.
But you're still saying that we choose to make up a story! That's still the causation that I'm talking about!
No! I'm not saying you choose! The person isn't lying. It's unconscious. Split brain patients do it all the time. They say they intended to draw the drawing they did, and they believe it, too. It's their brain that puts the story together, checking for global coherence. They're listening to the explanation the first time just when you are! And they believe it, even though you, the researcher, knows better about their own actions! It's crazy, but true!
Well, okay but still you're saying that the story's made up for us by our brain (whatever that could mean) and we are just attributing ourselves as the authors of the actions. Why would the laws of physics dictate that that should be so?
Beats me, I didn't set it up. That's just how it is.
But why would we make up a story about some things and not others?
Why not? We can't make up a story about everything…
But we only make up a story for actions that feel like we are controlling, like wiggling our finger as opposed to making our heart skip, yourself excluded.
Ah, that's just a homunculus. And who tells the brain to tell the story? And who tells the brain-teller? And the brain-teller's teller? It's an infinite regress. As the chain grows, the first person has to know and say an exponentially growing list of people to tell. Even the fourth homunculus down the line has to tell the brain-teller's teller to tell the brain-teller to tell the brain to tell the person that he wiggled his finger, not the laws of physics.
You lost me.
Think about it some more. Alright, never mind, I'll just stick with the last step in the process: why would the brain deceive us at all?
It's not trying to, it's trying to tell the truth!
And we're back to the homunculus.
What's the homunculus? Is that some weird philosophy thing?
Uh, if you don't know, it won't help to have it explained to you I'm afraid. At least not now. Let me go a different route. If it's trying to tell a story, and it always works out to be the most globally coherent story, than doesn't that count as evidence that the story is right??
You're assuming there's a "right" story.
No, you're assuming that, and I'm just going with it!
Because you're saying that there is a correct story—the laws of physics wiggled his finger—and that the person isn't privy to the real story. He's deceived, even if he knows the laws of physics, since he'll never be able to calculate them in time. Hey, that's interesting…if he could calculate fast enough, would he be able to predict his own motions?
Yeah, I suppose…
So will he be able to predict that he's going to predict what he's doing?
You're losing me again, I don't see how this pertains to the argument at hand.
It just shows that you're still supposing there's a real cause when we wiggle our finger and we are just not that cause…the laws of physics are.
Okay, so what are you saying?
I'm saying our body gives us good perceptions of cause. We cause our finger to move, and we feel ourselves deciding to and making that happen. We cannot do that with our heart, no matter how hard we concentrate. The difference is the difference between cause and not cause. Control and not control.
What about your lungs? Sometimes we control our breathing, and sometimes we don't! Is it an override, or a linear combination of neuron firings resulting in one action, or is it a nonlinear pattern of neuron firings…
Huh? Well, I don't know. I bet the breathing would be really interesting to study in terms of causes.
Or swallowing…You only start the muscles during swallowing…the rest happens automatically.
Yeah, you would know about swallowing, wouldn't you? Anyway, I'm saying that it's wrong to dismiss our biological basis for perceiving cause as 'animistic', whatever that would mean. It's important to take the things we're given and work with that. And we are given a front row seat to the decisions of our own actions. Even if we don't see every one, and sometimes we see things when they didn't happen, we are still remarkably reliable in being right about our own intentions. Not only can we perceive cause, we can perceive a single cause. That's something Hume could never do.
Yeah, well there's no such thing as a single cause. There's always a whole bunch of causes leading up to the action. For instance, each neuron causes the next one to fire, presumably. But we can't control a one of those!
That's true, that's a good point. But we can control the lot of them! It's a holistic thing. Besides, we don't have particular individual neurons as intentional objects. We do have the action as an intentional object—an object we can think about. That's the difference, I suppose, or part of it. The action has to be an intentional object, that is, a "think-about-able" thing.
Well, that doesn't seem right either. If your wiggling finger inadvertently hit a hidden launch button for a nuclear missile while it was wiggling, we have no reason to say that you did not decide to launch the missile. You only decided to wiggle your finger, but your wiggling finger did cause the missile launch. You didn't even have the missile as an intentional object but you did cause it to launch. The finger caused it to launch, but it can't hold any intentional objects in its mind because it doesn't have a mind of its own (despite what your girlfriend says, hey-o!)
Well, okay, I'll step that back a bit. I guess I'm just saying that actions that start as intentional objects and end as actions are an important case to study, since we see causation from the inside in those instances. Even if it's not perfect--we can be wrong about being the cause of our own actions if, for example, an electrode actually causes our finger to wiggle—there is still a fact of the matter to be determined. Then it becomes a problem of how to determine it, which leads us away from ontology and into epistemology.
Fair enough. Speaking of which, I have to take an epistemology right now…peace out! (she goes to the bathroom).