Friday, September 02, 2011

Thomas Reid, Champion of Common Sense, on the Immaterial Souls of Vegetables

Eighteenth century Scottish "common sense" philosopher Thomas Reid never tires of flogging his opponents with their violations of common sense. Thus, it may seem surprising that he would write this:

[B]oth vegetables and Animals are United to something immaterial, by such a Union as we conceive between Soul and Body, which Union continues while the Animal or Vegetable is alive, & is dissolved when it dies (in Wood, ed., 1995, p. 218-219).
In other words, vegetables have immaterial souls -- or, if not souls exactly, immaterial parts analogous to souls. (Not to worry, there's no Vegetable Heaven [see p. 223].) Although Reid doesn't highlight this point or dwell upon it, it flows very naturally from his general system on which nothing material can be the source of its own movement (including growth).

Because of Reid's reputation as the great philosopher of common sense, I'm examining his work as a test case of the following empirical hypothesis, which I currently consider to be well supported: No philosopher has ever been able to construct a detailed and coherent metaphysics of mind that entirely respects our commonsense intuitions. Not even Reid could do so. (Shall we try G.E. Moore next?)

The conclusion I'm inclined to draw, partly on its own merits and partly as the best explanation of this fact about the history of philosophy, is that our commonsense metaphysical intuitions are, at root, incoherent. Thus, there is no way to build a detailed and coherent metaphysics of mind that entirely respects common sense, making it unsurprising that none of the brilliant minds in the history of philosophy have ever done so.

Update, October 3:
Several people have reminded me in the comments that in Reid's era it might not have been contrary to common sense to suppose that vegetables have some sort of vital essence not wholly material. Reid's remarks about the immaterial souls of vegetables need to be seen in light of that. Still: It's a leap from some sort of vaguely folk-approved vital essence to an immaterial soul (or vegetative soul), and Reid does use the word "soul"; and he contemplates the question of afterlife for vegetables; and his view on these issues is tangled up with his view that physical objects and events have no causal powers of their own but require the constant intervention of immaterial beings -- a view that he explicitly confesses to be at odds with what most ordinary people would accept.

So: I still hold my view that Reid is not wholly able to preserve common sense on this matter, but the issue is more complex than I made it seem above.

33 comments:

Anonymous said...

Why do you think it's part of commonsense that vegetables don't have immaterial (vegetative) souls/parts?

John Sutton said...

Don't you think Eric that in the case of mind, 'commonsense intuitions' differ dramatically across times and places? This may be one such issue. I like the fact that Reid also thinks we have no better justification for claims about the past than for claims about the future - memory and foreknowledge are equally unaccountable and inscrutable to human understanding - is realism about the past part of common sense?

Clayton said...

I'm pretty sure that this is Richard Swinburne's view (although, in fairness, I'm sure he'd say that it is not).

Eric Schwitzgebel said...

@ Anon: We could run a poll: "Do vegetables have immaterial souls? circle one: yes/no" Of course, we'd have to do a little work to contextualize it so that people don't think it's just a joke. (Reid does say a little later on that vegetables do have souls, not just parts analogous.)

@ John: Yes, it's hard to know for sure what was "common sense" in the 18th century. But I suspect a careful search of the existing written literature will find most people attributing immaterial souls only to human beings, or maybe to human beings and animals, but only rarely to vegetables.

@ Clayton. Thanks for the tip on Swinburne. Would you recommend a specific place to look?

Clayton said...

That was sort of tongue in cheek. What he does is use puzzles of composition to argue that persons have immaterial souls and I like to remind my students that we can generate his puzzles using sticks of butter, ships, and vegetables. I believe it is in his -the evolution of the soul-

Christian Munthe said...

Eric, considering when Reid was active, one has, I think, count on the possibility that the immaterial 'thing' Reid talks about may not imply mind, consciousness or even sentience. It is quite possible that he employs the Aristotelian concept of a soul, which survived quite a long time due to Aquinas and subsequent dogma within scholastic philosophy. So, it may be that all he is affirming is the idea that, e.g., carrots have form in the Aristotelian sense. This seems to fit the notion of the immaterial aspect of carrots disappearing when the carrot dies.

Anonymous said...

I wonder if there's ANY philosophical theory "that entirely respects our commonsense intuitions". Perhaps the correspondence theory of truth does?

Unknown said...

If life forms operate strategically, then their strategies are a necessary part of the material that our forms are composed of. When for a myriad of possible reasons the strategies can no longer work, the forms that needed them for survival die. The same strategies will nevertheless be functional in related forms. (Not all of which are required to be alive to operate strategically, but that's another subject.)

Brian Fiala said...

Eric, you want to conclude that "our commonsense metaphysical intuitions are, at root, incoherent." Would you mind spelling out in a bit more detail just what the incoherence is supposed to be? In light of your comments in the second paragraph, I take it that part of what you're saying is that Reid's considered view of plant-souls violates a commonsense intuition that plants don't have souls. But I'm especially interested in the idea of a more direct kind of conflict between (or incommensurability of) intuitions here.

Also, I'm wondering whether you distinguish between the intuitive and the commonsensical, and if so I'm curious about the way in which such a distinction might figure in these matters. Here's an example of something that might be intuitive but not commonsensical: Arico et al. argue that it is intuitive that very simple animals like ants and spiders can experience pain, but this intuition seems to run against prevailing commonsense belief.

Richard Marshall said...

Hi Eric
Didn't Reid have a social epistemological take on consciousness whereby testimony is considered as essential to belief formation as perception, memory and so on, as opposed to the indiviudualistic epistemology of Descartes and Hume, where Hume, for instance, reduces testimony to individual perception? If so, wouldn't this support Christian's idea that he was taking an Aristotelian view about the soul rather than thinking it was some kind of mechanism for the mind.

Brandon said...

Eric said, in a comment above:

Yes, it's hard to know for sure what was "common sense" in the 18th century. But I suspect a careful search of the existing written literature will find most people attributing immaterial souls only to human beings, or maybe to human beings and animals, but only rarely to vegetables.

But it was considered common sense that nothing material can be the source of its own movement (the number of people in the period who not only insist on this but insist on its being a quite obvious and indisputable claim is extraordinary), and as you noted in the post, the immaterial vegetable souls position quite naturally follows from this with minimal assumptions. This sort of case could just as easily be taken as saying that people are often not consistent with their assumptions (with philosophers like Reid catching them out on it) as it could be taken to say anything about commonsense metaphysics.

In any case, I worry somewhat about the phrase 'common sense' here; it means something quite specific and at least semi-technical in Reid (it's literally an internal sense, and he has an epistemological account of how it works and why we must rely on it), and shouldn't be confused with 'common, everyday assumptions'.

Eric Schwitzgebel said...

@ Clayton: Okay, thanks!

Eric Schwitzgebel said...

@ Christian: Yes, I am reminded of the scholastic "vegetative soul". I believe Reid does deny that vegetables think. Still, it seems to me very likely that common sense, even in Reid's time, would reject the idea that vegetables have immaterial souls.

Eric Schwitzgebel said...

@ derblindehund: It does seem to me that most philosophical theories cross against common sense when developed in detail. Vague, undeveloped philosophical views are less likely to jar against common sense. Whether *all* philosophical theories violate common sense if developed in detail I'm unsure, but it does seem to me possible that that is the case if "philosophical theory" is construed narrowly enough. Even the correspondence theory of truth starts looking weird in the hands of people who try to work out the details (e.g., in Wittgenstein's Tractatus).

Eric Schwitzgebel said...

@ Roy: Okay, maybe so. I'm not sure what you think the implications are, if any, for the commonsensicality or not of Reid's view.

Eric Schwitzgebel said...

@ Brian: That's a very interesting article and part of the general background of work that I interpret as supporting the incoherence view. I prefer "common sense" here to "intuitive" because "common sense" nicely suggests that the view is ordinary and widespread (whereas different people, especially philosophers, may have different "intuitions") and because "common sense" judgments reflect one's considered endorsement whereas an "intuition", one might worry, can come fast and not be fully endorsed by the agent. (Though people like George Bealer who valorize philosophical intuition would not agree with that last claim.)

I believe that common sense may be ambivalent or underdetermined on the issue of whether insects feel pain.

A view is "incoherent" in the sense I intend if one could derive a contradiction from the propositions constituting that view.

Eric Schwitzgebel said...

@ Richard: Maybe so. But doesn't it still seem a violation of common sense to attribute immaterial souls to vegetables? To be clear: I'm not saying that one couldn't *come* to that view by reflection that starts from commmonsense premises. In fact, I think that one probably could -- thereby displaying and instance of the incoherence of common sense on the metaphysics of dualism (if I am correct common sense rejects the immaterial souls of vegetables).

Eric Schwitzgebel said...

Brandon: I think I agree with both of your points. Specifically:

(1.) Yes, it could be an incoherence in common sense. If common sense (at least in Reid's period) was committed to (a.) nothing merely material can generate its own motion, (b.) vegetables can generate their own motion, and (c.) vegetables are wholly material, then common sense was incoherent. So Reid, if he is to have a coherent view in this area, will have to reject one of the three conjuncts.

(2.) Reid does of course have a view of common sense. I don't mean to be using Reid's technical definition of the term but rather a "common sense" understanding of what common sense is!

Richard Marshall said...

Eric

I wonder if the more we mention the idea of vegetables having immaterial souls the less inclined we become to reject it on common sense grounds. Is this a problem for common sense studies, and so for crazyism too, that initial ideas that seem contrary to common sense or crazyism become less so the longer we are exposed to them? For example, Dan Dennett's ideas about the illusion of qualia seemed crazy before but by now we take it as just part of what is on the table about consciousness and doesn't seem antithetical to common sense any more.

Eric Schwitzgebel said...

Richard: I agree that common sense does evolve and probably that mere repeated exposure to a view can help it seem less in conflict with common sense. However, we probably disagree about the pace at which this happens. Also, I think common sense needs to be defined relative to a population of non-specialists, whereas you seem to be thinking of it here as something relative to an individual including an individual specialist.

Jakob Hohwy said...

Some, such as Wheatstone, seemed to think already then that Reid was relying too much on common sense. Reid had claimed that two different colors presented one to each eye would not rival, and Wheatstone took him to task: "Reid made an inconsiderate error, which arose no doubt from … deciding according to previous notions, instead of ascertaining by experiment what actually does happen" (p387)
Wheatstone, C. (1838). Contributions to the physiology of vision. Part I. On some remarkable, and hitherto unobserved, phenomena of binocular vision. Phil. Trans. R. Soc. Lond. B, 128, 371-394.

Eric Schwitzgebel said...

Thanks for the comment, Jakob! A related issue on which Wheatstone and Reid disagree, but which (oddly) seems to cut the opposite direction vis-a-vis common sense, is this: Reid thought that the binocular visual field was pervasively doubled off the horopter whereas Wheatstone rejected that. That last fact is particularly interesting to me given Wheatstone's invention of the stereoscope and my conjecture [Perplexities, ch. 2] that analogizing visual experience to the stereoscope would relate positively to attribution of doubling off the horopter.

Kurt M. Boughan said...

I'm very late to this party and you may no longer be paying attention, Eric, but I'm basically with Christian. Reid's statement sounds entirely Aristotelian; i.e., plants have a vegetative soul, namely a form that is the actualization of the powers of nutrition, growth, and generation in some suitable matter.

I don't know whether that would be weird or inconsistent thing for Reid himself to say (he's far too late to interest me), but it doesn't sound particularly weird per se. The "union" would seem to be just Aristotle's hylomorphism.

And not at all weird.

Eric Schwitzgebel said...

What, late medieval scholastic metaphysics isn't weird? I thought that's why you liked it! ;-)

Anonymous said...

I don't think Aristotle would have had much problem with this idea, and neither do I. If we're prepared to read "soul" as "animating principle," there's fairly little to get bothered about. Specifically, that they "have immaterial parts analagous to souls" is not a shortcoming--it is a feature. All living things have souls or animating principles of some sort; that is what life is.

Reid hints in this passage, but does not explicitly claim, that the "animator" might be durable; that not its existance, but only its union with the living thing is terminated at death. Well, it was a backward and a superstitious age.

Eric Schwitzgebel said...

Yeah, I'm slowly coming around. Maybe immaterial souls for vegetables isn't quite as weird as it seems at first blush, if you think about the attractions of animism and vital essence.

But I still think: (1.) It's probably at least somewhat weird, even in historical context. And (2.) Thinking it through will likely end up committing you to further weirdnesses as you work out the details, e.g., about what happens at death. The scholastics, as I understand it, really struggled over that one!

Anonymous said...

This is a poor argument. There are countless examples of cultures assuming that any living - or even non-living - entities have immaterial parts. Try again.

Eric Schwitzgebel said...

As I said in response to previous comments, I'm softening on this. The idea of some sort of vital essence in plants that transcends the material might be fairly cross-culturally common. But still: Let's do a worldwide poll of all time: Vegetables have immaterial souls, y/n? Care to take bets? And Reid does say "soul": I should have been more explicit about that in the post.

It's one thing to think there might be some mysterious vitality, not entirely material, another to posit a soul.

Alan Tapper said...

This discussion is missing what Reid meant by common sense. For Reid, a belief is "common sense" only if it is held by all sane adults except when they are doing philosophy. So for Reid it was not a proposition of common sense that vegetables have souls, even if he did believe that proposition.

Eric Schwitzgebel said...

Alan: I agree that Reid probably did not regard the view as common sense, although I don't believe he explicitly denies that it is common sense. (If you know of a passage where he does, I'd be interested to hear.) It is a further question whether the view violates common sense (since common sense might be neutral).

My interest in the question turns on whether it is possible to construct a detailed dualistic metaphysics of the mind-body problem that thoroughly respects common sense. One might think that Reid would have been a good candidate to have done so, if anyone could. But I don't think he did so.

Alan Tapper said...

Reid defined common sense most carefully in his Essays on the Intellectual Powers of Man (Essay VI). He thought there were twelve first principles of common sense, though he was open to debate about them.

Neither mind-body dualism nor theism are included in his list. Rightly, since he could see that sane people had differing views on these, even when they were not doing philosophy.

I recommend Philip de Bary's book, Thomas Reid and Scepticism, which grapples with Reid's philosophical strategy.

The passage which you quote on vegetables comes from his unpublished manuscripts. Those papers are not trying to define the scope of common sense.

As it happens, I've written a paper, Reid and Priestley on Method and the Mind, Phil Quarterly 2002, that argues for your opinion that Reid did not find a coherent basis for dualism. (Also in Haldane and Read, The Philosophy of Thomas Reid, 2003.)

Alan Tapper said...

Also worth reading, and free online, is Rebecca Copenhaver, Was Reid a Mysterian?

http://legacy.lclark.edu/~rebeccac/mysterian.pdf

Eric Schwitzgebel said...

Thanks for the refs, Alan. Very useful!