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? Remarkable! But I guess it is not so remarkable if we
keep in mind the 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 not 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
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
"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:
Plants are responsive to "sense" impressions
As defined in the dictionary, anything responsive to sense impressions
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.
Plants are sentient
Sentient beings are conscious of sense impressions
Plants are conscious of sense impressions
To be conscious of a noxious stimuli is felt as unpleasant
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
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
behaviors. The Oxford English Dictionary lists 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
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 bluntly
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
4. Error #4: REMOTE PARALLELS DO NOT MAKE 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 signaling
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
behavioral 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 a
bootleg false conclusion, or we simply have a re-definition 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 behaviors and
not the means and enabling conditions for those behaviors.
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 that particular disease there were
no pains or discomfort of any kind, whereupon our hypochondriac gasped,
"I knew it, my symptoms exactly!"
* Dreyfus, Hubert L. (1987). Misrepresenting human intelligence. In
Rainer Born (Ed.), Artificial intelligence: The case against. London:
* 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:
* Taylor, Charles (1964). The explanation of behavior. London: Routledge
& Kegan Paul.
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