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Newsgroups: rec.food.veg From: altar@beaufort.sfu.ca (Ted Wayn Altar) Subject: Plant Pain Message-ID: <altar.724697657@sfu.ca> Sender: news@sfu.ca Organization: Simon Fraser University, Burnaby, B.C., Canada Date: Fri, 18 Dec 1992 16:54:17 GMT Lines: 389

[This document contains both parts concatenated.]

I see that the old chestnut of "plant pain" has again been invoked. Apparently, this is a common argument and so, dear reader, permit me to re-post an older message of mine that attempts to address this issue in a discursive, but also humourous manner.

Happy Holiday Season,

ted

THE DIVERSIONARY TACTIC OF PLANT PAIN

TED ALTAR

A. HOW MIGHT CHARLES DARWIN RESPOND?

With respect to this extravagant debate on plant pain we have at hand a most promiscuous adjoining of some verified facts with improper inferences. This reminds me of a story (probably apocryphal as are so many of the best anecdotes) about Charles Darwin who in his later years was the guest of a family whose two boys approached him with a clever deception. Using some old desiccated specimens of insects, they had deftly attached the wings of a butterfly, the head of a beetle and the legs of a grasshopper to the body of a centipede. "We have this strange bug we caught some time ago" they innocently said, "Can you tell us what it might be?" Darwin squinted and examined it as best he could and asked, "Can you remember if it hummed when you caught it?" he asked in all seriousness. Without smirking, the boys answered yes, whereupon Darwin replied, "Just as I thought, it is a humbug!"

B. THE SPECIOUS INFERENCE OF PLANT PAIN.

No doubt we all have been amazed by much "humbug" on this conference, but maybe no greater example is to be given than that of "plant pain". Those whose common sense remains intact will have no difficulty in accepting as sufficient the following:

1. Our best science to date shows that plants lack any semblance of a central nervous system or any other system design for such complex capacities as that of a conscious suffering from felt pain.

2. Plants simply have no evolutionary need to feel pain. Animals being mobile would benefit from the ability to sense pain; plants would not. Nature does not create gratuitously such complex capacities as that of feeling pain unless there should be some benefit for the organism's survival.

Well, as Oliver Goldsmith realistically observed, "Every absurdity has its champions to defend it". And yes, we have some defenders who would ignore common sense and argue for plant pain. Remarkable!. But maybe not so remarkable if we keep in mind the motivation for such humbug. The following argument has repeated been voiced against the concern of us who would forward greater regard for the woefully neglected and grievous suffering of those sentient creatures who cannot defend, nor articulate in words, their plight. The following `reductio ad absurdum' is supposed to suffice as an irrefutable trashing of animal rights.

Premise(1) If a sentient being can consciously experience pain and suffering, then it is wrong to inflict pain & suffering on such a sentient being Premise(2) Plants are sentient beings that can experience pain & suffering Conclusion: It is wrong to inflict pain & suffering on plants.

In order to challenge the acceptability of premise(1), the anti-AR would have us believe that such a premise ineluctably leads to the absurd conclusion as stated above. In order to achieve this coup de grace of animal rights, the anti-AR who would give little or no coin to premise (1), would instead introduce the claims of premise(2) as somehow "scientifically established". In order to debunk animal rights as foolish, the anti-AR would first have us believe in the reality of "plant pain". Hence, they would attempt to bury AR into a hole but ironically by first bulldozing a much deeper one for themselves.

E. "EVERY ABSURDITY HAS ITS CHAMPIONS TO DEFEND IT"

You say that I am merely spinning my wheels on a straw man? Then permit me to quote from two of the most loquacious and articulate promoters of plant "pain" on this conference.

Poster A would bait us with the following argument, an argument that presumably he still holds as having merit by virtue of his repeated postings of this worn polemic:

AR: "You're crude and unfeeling; you'd probably laugh at your mother's death." non-AR: "That's silly, my mother is a human. A deer isn't." AR: "Deer can suffer, and so do cattle...so I don't eat meat." non-AR: "You apparently have no problem killing plants, though." AR: "It's not the same. Plants aren't animals." non-AR: "You're killing a living thing for food, nevertheless." AR: "But it can't feel; it's not sentient; it has no nervous system." non-AR: "Does dissimilarity rule out 'pain'?" AR: "Yes." non-AR: "That's completely illogical and unscientific."

Note how Poster A would invoke the authority of logic and science as "completely" on his side. Next, consider the assertions of Poster B:

As a plant molecular biologist with quite a few refereed papers on the subject of cellular communication in plants, please allow me to debunk the unsubstantiated mythology described above. Plants have no *need* to feel pain? Ridiculous.

When a plant is attacked by an herbivorous insect, might it not be in the best interest of the plant to mobilize its chemical defenses in other parts of the plant in anticipation of further insect attack? When a leaf is infected by a pathogenic fungus, might the rest of the plant wish to bolster its chemical and enzymatic defenses against the spread of the pathogen? News flash -- the plant *would* benefit, hence the development of a systemic (throughout the plant) response to local tissue damage by herbivores and pathogens. (Many) references available upon request. It might easily be argued that *because* plants can't move they need effective chemical defenses and effective detection and communication. This is the case. You may doubt the sensory and integrative abilities of plants, so I invite you to spend a few weeks in my lab and learn the truth. Plants don't have nerves, since they don't share a particularly recent common ancestor with animals. Plants feel tissue injury and respond quickly, precisely, and with an effective battery of defenses. They don't feel *like us*, but it would be a mistake to say that they *don't feel*.

Here we have the authority of logic, science and "truth" being imprecated against the sorry state of AR nescience and "mythology". Yet, no single published book, or paper in a scientific journal, has been cited as indeed making this claim that "plants feel pain". Sure, there is interesting evidence about plants reacting to local tissue damage and even sending signalling molecules serving to stimulate certain chemical defenses of nearby plants. But what has this got to do with supporting the only morally relevant claim worth considering, namely that "plants FEEL AND SUFFER from pain"? Where are the scientific references for this putative fact?

Now, dear reader, please be patient with my indulgence to develop a reasoned reply to such assertive and authoritative pronouncements about plant pain.

C. A REDUCTIO ON A REDUCTIO

Although the plant pain promoters are fond of reductios, they will not likely appreciate the following extension of their own. By their "logic", it would equally be the case that rain clouds behave purposefully in the sense that they could be said to functionally remove, by way of raining, excessive moisture that is causing their overstaturation. Furthermore, rain clouds bear meaningful information about their level of oversaturation in the form of weight relative to volume. Do not clouds, therefore, "sense" (in some tortured notion of the word) when atmospheric pressure is insufficient for their moisture content to remain in a vaporous state? The promoters of plant pain would have us believe, against our good common sense, that by the mere presence of purposive BEHAVIOURS of avoidance and REACTIONS to tissue damage in plants we therefore must attribute to plants mental states like that of some kind of "felt pain". Well, then by the same logic we must do the same to clouds. In the hole that these promoters of plant pain would dig for themselves, not only must we accept the thesis of plant pain, we would also have to swallow some notion of "cloud sentience"!

D. THE BEHAVIOURAL INFERENCE OF MENTAL STATES

Lest we forget the ultimate point of what follows, let us not forget the central thesis of AR. Simply stated: to the extent other animals share with us, at least to some degree, certain morally relevant attributes, then to that extent we cannot ignore, for the purposes of consistency or justice, giving due regard and concern towards those animals. Two attributes that are arguably relevant are:

1. our commonly shared interest in the avoidance of pain and suffering.

2. and the quality of other animals also being subjects-of-a-life which matters to them as to how such a life fares well or ill.

Both these qualities posit other animals having certain mental states. Also note that in order to speak of "mental states" proper, we would denote, as common usage would dictate, that such states are marked by consciousness. It is simply insufficient to mark off mental states by only the presence of purposefulness or intentionality since many objects, like thermostats and hand calculators, possess purposeful-looking behaviours or are in an information- bearing state.

Let us further observe that the attribution of morally relevant mental states to even humans was at one time an issue of contention. For example, consider the case of that very prestigious scientific apologist of his society's ambient prejudices, Silas Mitchell, founder of American neurology. He claimed that civilized men suffered pain in a far more ethically relevant manner:

"In our process of being civilized we have won . . . intensified capacity to suffer. The savage does not feel pain as we do" [1].

Today, we can witness a similar prejudice that animals do not suffer pain to the same capacity as we do. For instance, a cow after surgery will right away start eating grass, therefore it will be said that the cow cannot be suffering from post-surgery pain. Just as with the stoic "savage", who is to say that a cow is not likewise simply bearing the pain more "heroically" since, as with the non- civilized human, food is more of an imperative than moaning with pain; indeed, what else can they do?

So then, how do we properly attribute the existence of mental states to other animals, or even to ourselves for that matter, since in the past we have certainly made mistakes on this score? As we have seen, the *criterion of outward functional behaviour* has been faulty with even humans. Yet, our plant pain promoters would employ this same criterion at a different level, turn things on their head and argue that because plants react to noxious stimuli, they therefore feel pain. Now, if the inference of pain from overt behaviours has been faulty for attributing pain where we now know pain most assuredly exists, then it is probably equally faulty in attributing pain where pain does not exist. If reactions or behaviours were sufficient, then we would have to say that a mere toy doll crying and wriggling, when triggered to do so by certain stimuli, was indeed in pain.

Similarly, we cannot infer the presence of felt pain simply by the presence of a sub-class of behaviours which are functional for an organism's amelioration or avoidance of noxious stimuli. Thermostats obviously react to thermal changes in the environment and respond in a functionally appropriate manner to restore an initial "preferred" state thereby maintaining an equilibrium of the status quo. We would be dirt foolish, however, to then attribute to thermostats that therefore they must "sense" or "feel" some kind of "pain". Even warning quotes around our terms don't protect us from such an catachrestic absurdity.

Clearly, the behavioral criterion of even functional avoidance/defense reactions, is simply not sufficient nor even necessary for the proper attribution of pain as a felt mental state. This is not to say that it is completely irrelevant for it can at least index the presence of pain in those creatures we already know or have good reason to believe experience and suffer pain. Behaviour by itself does not index pain in our toy doll or thermostat, but behaviour does usefully index the occurrence of pain and suffering in those animals that we already have reason to believe have the capacity to suffer.

E. THE RELEVANCE OF SPECIALIZED STRUCTURE

To state the obvious, science, including the biological sciences, are generally committed to the working assumption of scientific materialism or physicalism [2]. Now, unless the "new" biology has returned to some arcane version of vitalism or dualism, then we must start with the generally accepted scientific assumption that matter is the only existent or real primordial constituent of the universe.

Let it be said at the outset that scientific materialism as such does not preclude the existence of emergent or functional qualities like that of mind, consciousness, and feeling (or even, dare I say it, free will), but all such qualities are dependant upon the existence of organized matter. If there is no hardware, there is nothing for the software to run on. If there is no intact, living brain, there is simply no mind. Now, just for the record it should also be said that even contemporary versions of dualism or mind-stuff theories will also make depended their embodied mental states in this world on the presence of sufficiently organized matter.

To briefly state the case, what is referred to as non- reductive materialism [3] would simply consider cognitive functions like consciousness and mind as emergent properties of sufficiently organized matter. Just as breathing is a function of a complex system of organs referred to aggregately as the respiratory system, so too is consciousness a function of the immensely complex information-processing capabilities of a central nervous system. Now, according to such a neo-functionalist account of mental states, HOW the matter is organized and in with WHAT materials is not necessarily delimited to the mammalian brain. It is possible in theory, that our Alpha Centaurians who evolved from carrots could equally instantiate some "higher" functions of consciousness. This may even be possible with a future computer given a sufficiently complex and orderly organization of its hardware and clever software. While such a computer does not yet exist, and we don't yet know about those Alpha Centaurians, we DO know that certain living organisms on this planet do possess the requisite complexity of specialized and highly organized structure for the emergence of mental states.

In theory, plants could possess a mental state like pain, but IF, AND ONLY IF there is a requisite complexity of organized plant tissue which could serve to INSTANTIATE the kinds of complex information processing that is prerequisite to such higher order mental states as that of consciousness and felt pain. A mammalian brain is not necessary but an immensely complex hierarchically organized central processor of some form would be.

Now, where is the morphological evidence that such a complexity of tissue in plants exist? Single cells or even aggregates of surrounding tissue is not sufficient for there to be a functional state of felt pain any more than even todays complex integrated circuit chips evince consciousness of any kind. A lot is required and plants just don't have it. This is not to say that they cannot exhibit complex reactions, but we are simply OVER-INTERPRETING such reactions when they are designated as "felt pain".

With respect to all mammals, birds, and reptiles, we know that they possess a sufficiently complex neural structure to enable felt pain plus an evolutionary need for such consciously felt states. They possess complex and specialized organizations of tissue call sense organs, they possess a specialized and complex structure for processing information and for centrally orchestrating appropriate behaviours in accordance with mental representations, integrations and reorganizations of that information. The proper attribution of felt pain in these animals is well justified, but it is not for plants by any stretch of the imagination.

ted

I. REFERENCES

[1] Cited from M. Pernick's (1985) "A CALCULUS OF SUFFERING: PAIN, PROFESSIONALISM AND ANESTHESIA IN 19TH C. AMERICA. New York: Columbia University Press. Cited in turn in Bernard Rollin's (1989), "THE UNHEEDED CRY: ANIMAL CONSCIOUSNESS, ANIMAL PAIN AND SCIENCE". Oxford: Oxford University Press. I would strongly recommend Rollin's book as a very well argued and documented scholarly work on this important issue.

[2] Burtt, E. A. (1924). THE METAPHYSICAL FOUNDATIONS OF MODERN SCIENCE. London: Routledge & Kegan [3] See Flanagan, Owen's THE SCIENCE OF THE MIND (2n ed). Mass.: The MIT Press. Provides for a good review of these issues. THE FALLACIES BEHIND THE PLANT PAIN ARGUMENT

Many are destined to reason wrongly, others, not to reason at all; and others, to persecute those who do reason. (Voltaire)

How, then, could anybody seriously entertain this humbug of plant pain? Is it not remarkable that the most persistent and articulate of the anti-AR would forward such contentious and prima facie absurd claims. But I guess it is not so remarkable if we keep in mind their dogged intent to debunk the claims of animal rights, seemingly no matter at what cost to good sense, rationality, or even established scientific fact. Since, as we have seen, many would claim to be avowed ethical subjectivists, at least when it is convenient to do so, I guess we should not be surprised that rationality and intellect is merely made sullied handmaidens for advancing their quest to discredit the case for animal rights.

What follows, dear reader, are five of the common flaws of reason masquerading as arguments on behalf of plant rights.

1. Error #1: THE ARGUMENTUM AD IGNORANTIUM

In the name of open-mindedness, we are asked to take seriously the claim of plant pain because the disbelievers and the incredulous simply cannot prove that plants have no felt pain, or that our knowledge of such things as with many other things, is simply incomplete and uncertain. For instance, it has been said that:

"The simple fact that "cruelty" cannot be DIS-proved introduces reasonable doubt into this argument."

Here we have the presumption of innocence found in a court of law being inappropriately transferred to how scientific theories are to be established or seriously entertained. Normally, we would argue on BEHALF of a scientific theory by presenting evidence for it, not by pointing to our current lack of evidence unless one is arguing AGAINST a theory. The plant pain promoters would turn the logic of scientific justification on its head.

Now, in a general or ultimate sense it is TRIVIALLY TRUE that there is no final "proof" against such wild notions, but then there is also no ultimate proof against unicorns or ghosts. It is a well known INFORMAL FALLACY to conclude from a lack of disproof for something's existence that it therefore exists or must be taken as a serious possibility for existence. That is to say, it is simply false to argue that a proposition is true simply on the basis that it has not been proved false. The idea here is to try to persuade people of a proposition which avails itself of facts and reasons the falsity or inadequacy of which is not readily discerned.

This flawed logic is technically referred to by logicians as the "ARGUMENTUM AD IGNORANTIUM" (argument from ignorance). This is a logically invalid argument, one that would exploit our common ignorance of things. Now, you might ask, why shouldn't we permit speculative theories to enter into our foundation of ethics. Consider, however, the following example:

"no breath of scandal has ever touched the mayor, therefore she is MUST be incorruptibly honest".

Maybe she is and maybe she is not, but our ignorance does not establish the truth or falsity of the conclusion that she is incorruptibly honesty. It is simply unfair to employ our ignorance as the sole basis of support for some social/public concern.

Similarly, what we DO KNOW about how animals experience pain and suffering is of relevance for a system of public ethics. What we do know about plants is that they DO NOT HAVE a nervous system nor a structure at the cellular level designed to process information in a manner that would conceivably enable a conscious suffering of pain or discomfort. What we do NOT YET KNOW about the workings of plants, of how consciousness in general is enabled, or of how the universe as a whole works, is simply not relevant. It is one thing to plea for open-mindedness, it is quite another to promote intellectual promiscuity under the same banner.

2. Error #2: EQUIVOCATION OF TERMS TO BOOTLEG A FALSE CONCLUSION

To understand this very slippery and flawed reasoning that logicians refer to as the informal fallacy of EQUIVOCATION, consider the following example:

"The end of a thing is its perfection; death is the end of life; hence, death is the perfection of life"

Note the two senses of the word "end" and how the last part of the sentence confuses them. The word "end" may mean either "goal" or "last event". Both meanings are legitimate, but to confuse the two in an argument is a fallacy. In the example above we have two legitimate premises but a false conclusion that does not follow from the premises, unless we remove the equivocation and rewrite, say, the first premise as:

"The LAST EVENT of a thing is its perfection".

But such a premise is patently false.

This is exactly the kind of flawed argumentation that is occurring with our promoters of plant pain. For instance, the term "sentient" is deemed applicable to plants given ONE of its meanings to simply be the "responsiveness to sensory stimuli". After arguing further that what plants do at a molecular level can be deemed a "sensory response", even thought they do not possess specialized organizations of tissue called sense organs (see error #3 below), they would then have us accept the designation that plants are "sentient".

Let us, for the sake of argument, accept their twisted meaning of the term of "sentient" to simply mean a functional reaction on a biochemical or cellular level to noxious or warning stimuli. In this sense, they will argue that a plant can be said to be "sentient". But at a different juncture they would then have us conclude that because plants are indeed "sentient" they also "feel" tissue injury or assault as "unpleasant"! What the wily plant pain promoters have done is simply bootleg a false conclusion by switching between two quite difference meanings of the word "sentient". Permit me to lay it out:

premise 1: Plants are responsive to "sense" impressions premise 2: As defined in the dictionary, anything responsive to sense impressions are sentient conclusion 1: Plants are sentient

Note that premise 1 employs the word "sense" in a very restrictive manner to mean, for the plant pain promoters, "reactions to certain stimuli". Now, for them to jump from this minimal and idiosyncratic usage of "sentient" to the issue of plant pain, our wily abusers of ordinary language IMPLICITLY are forwarding something like the following argument.

conclusion 1: Plants are sentient premise 3: Sentient beings are conscious of sense impressions conclusion 2: plants are conscious of sense impressions

premise 4: To be conscious of a noxious stimuli is felt as unpleasant conclusion 3: noxious stimuli to plants is unpleasant

From unpleasant we then arrive at plant pain. Of course, our plant promoters will protest that they never said that plants have "consciousness" or "feel" pain, but only that they respond in a manner similar to how we respond to pain. Well, if that be truly the only claim and no more, then there is simply no relevance whatsoever of such an idiosyncratic notion plant "pain" to the real ethical issue of animals suffering from felt pain. If it is not irrelevant, then we have either one of 2 results:

1. equivocating on usage of "sentient" to bootleg a false conclusion. This is a logical, not a semantic, fallacy.

2. redefining what ordinary people mean by pain and suffering so that these terms no longer refer to a conscious awareness of pain/suffering. Now we have the error of irrelevant re-definition. This brings us to the next error of reasoning.

3. Error #3: LOGOMACHY OR "LET'S PLAY RE-DEFINITION"

. For most people, "sentient" designates the capacity to feel. That is, it would refer to a mental state, not a mere set of behaviours. The Oxford English Dictionary list 3 core meanings, of which the plant pain promoters will selectively choose only one, it being the most minimal definition, namely:

"def 2: Phys. Of organs or tissues: responsive to sensory stimuli."

Of course, they do not look any further. If they were, they might be surprised to discover that the word "sensory" refers to the organs of "sense" or belonging to "sensation" In turn, the words "sense" and "sensation" refers to the organs or mental states of perception, of psychical affection, of consciousness, etc. Indeed, it is designated right at the beginning that "sensation" is "now commonly the subjective element in the operation of the senses; psychical feeling" (OED). The meanings that predominate refer to mental states, and as we have noted, all mental states are marked by consciousness. Yet, our plant pain promoters ignore these obvious conventions of ordinary word meanings and would legislate their own. And what motivates this re-definition of our terms? Certainly, not to promote clarity or scientific accuracy. If plants have "pain" but no consciousness then what are we to make of such muddy oxymorons as that of an "unconscious pain" or an "unfelt pain"?

If our promoters of plant pain weren't so blunt serious, this might all be very funny. Indeed, good puns and amusing gaffs result from an incongruous and inapposite word usage. For example, someone once stole the seats from all the toilets in a Canadian RCMP station. The official press release by the Mounties said that they still had nothing to go on. Methinks our pain promoters also have nothing to go on.

4. Error #4: REMOTE PARALLELS DO NOT MAKE FOR IDENTITIES

Now, we have been entertained by our plant pain promoters of some interesting facts like that of oak trees diverting some of its activity to an increase production of tannic acid in respond to, say, a Gypsy moth invasion. We are informed that:

> There IS a parallel here, and the relative complexity of the > sensory and interpretive mechanisms is irrelevant.

The cruel fact remains, however, that PARALLELS DO NOT MAKE FOR IDENTITIES. Indeed, how something is achieved is just as important as what is being achieved in order to properly attribute there to be identity. For animals, conscious motivation to avoid pain figures very large in how they would avoid or mitigate pain. Pain is not something that is unfelt. It makes no sense to speak of "unfelt, unconscious pain", yet our plant pain promoters will insist upon there being a morally relevant parallel.

To illustrate this point about identity, please permit me to work from a different and more familiar example. Now, it has been argued that computers "think" as evidence by their capacity to manipulate symbols. What shall we make of this?.

Searle's (1980) well-known Chinese room argument, however, at least makes clear that computers as syntactic engines are not "understanders" of language even if they should one day be successful at translating from Chinese to English back to Chinese. The subjective life and mind accompanying a person's performances would seem to involve more than the computer's superior efficiency at manipulating data according to sequences of algorithm-governed operations. To even here speak of "rule- governed operations" is misleading since it suggests we can talk of these machines under the description of them "following rules". Shanker (1987) makes the case that this violates our logical grammar of rule-following being a normative rather a mechanical action and that it is an action predicated on some necessary minimal "understanding" of the rule. Due to the literal ascription implied by this trope about computers, we are lapsing into the same kind of conceptual confusion that would occur if we were to literally ascribe to the members of a meeting that they were following Robert's rules of order even though they were ignorant of, or did not understand the rules. If we were to say such a thing, it would only be FIGURATIVE for simply saying that the members just happen to be inadvertently or unknowingly abiding by Robert's rules. Notwithstanding the generosities of idealization and wishful rhetoric, the computer analogue still remains a metaphor and one that too often invites a misleading anthropomorphism (Dreyfus, 1987).

Indeed, as the problems of the computer metaphor are becoming more widely appreciated and, as Michie (1982) notes, the former heuristic value of the metaphor is being replaced by more exact and fruitful formalizations and mathematics, the metaphor is beginning to become less frequent in the scientific prose of AI science itself. While anthropomorphic speculation inaugurated both the animal and computer models, it is a circumspect anthropomorphism tempered with naturalism that now appears to be the most fruitful approach for the understanding of animals (Griffin, 1981), but it is an "objectivist", or more precisely an electrical-mechanical and symbolic-mathematical prose, that is more fitting for AI. With respect to plants, the language of mental states is simply addleheaded and daft.

5. Error #5: OVER-INTERPRETATION OF ESTABLISHED FACTS

Now, we have been told that "there IS some evidence which shows that plants are "sentient", in the broad sense of the word." Hmm., more likely the narrow and twisted sense of the word. But again, all we have is simply the interesting but morally irrelevant facts about plants reacting to certain noxious stimuli, or to the signalling molecules of other plants under attack. We are then asked about how this might be different from our own sense of smell. They would ask, "is this not equivalent to plant sensation or of a plant sensing its environment?" By now, we should be able to readily reply that such usage simply stretches our ordinary definitions of the word "sense". Mere behavioural reactions and avoidance to certain stimuli is insufficient for the attributions of mental states like that of perceptions and knowing sensation. Again, we have either an equivocation of usage to bootleg false conclusion, or we simply have a re-defninition of our ordinary meanings to something idiosyncratic and morally irrelevant. HOW the plants do what they do is just as important as the function of what those reactions subserve.

Here is an example of over-interpretation that was due to this error of only observing the end result and not the means. It was once thought that army ants were comprised of a strategic military column marching through the forest with direction, purpose and foresight. Well, it turns out that these ants simply follow the smell of the ants in front, and in turn the leading ants simply, in a somewhat random manner, lurch or are, pushed forward. If these ants were to be placed on a flat surface and the leading ants were to make a circle back to the rump end of the column, the marching column of ants would simply go around and around until they died. Where is the intentional purpose, planning and foresight? There is no scouting ahead of the terrain, no deliberative leadership, just a very simply mechanism that under normal conditions in the uneven terrain of the forest works very effectively to keep the ants ever moving forward in search new food supplies. The key point is that for many centuries people over-interpreted what was going on simply because they only observed the overt functional behaviours and not the means and enabling conditions for those behaviours.

6. THE BELIEF IN NON-EXISTENT PAINS. :-)

Patient reader, permit me to finish with one last observation. Hypochondriacs are, as you know, people who believe in pains that simply don't exist. This much they have in common with our plant pain promoters. Of course, hypochondriacs also are easily persuaded that they must themselves have what even the most superficial description of an illness would describe. I'll leave it to the reader to decide if this parallel also applies to our plant pain promoters. Now, there is the amusing story of one such person who after hearing a lecture on diseases of the kidney, immediately phoned his doctor. The good doctor patiently explained that in that particular disease there were no pains or discomfort of any kind, whereupon our hypochondriac gasped, "I knew it, my symptoms exactly!" :-)

ted

REFERENCES

Dreyfus, Hubert L. (1987). Misrepresenting human intelligence. In Rainer Born (Ed.), Artificial intelligence: The case against. London: Croom Helm. Griffin, Donald R. (1981). The question of animal awareness: Evolutionary continuity of mental experience (2nd ed.). California: William Kaufmann. Another good book that I would highly recommend. Michie, Donald (1982). Machine intelligence and related topics. London: Gordon & Breach Science Publishers. Searle, J. (1980). Minds, brains, and programs. Behavioral and Brain Sciences, 3, 417-457. Shanker, S. G. (1987). The decline and fall of the mechanist metaphor. In Rainer Born (Ed.), Artificial intelligence: The case against. London: Croom Helm. Taylor, Charles (1964). The explanation of behaviour. London: Routledge & Kegan Paul.