And What About Plants?

Posted by Sherry F. Colb


Last month, Natalie Angier wrote an article in the New York Times about new research suggesting that plants have active and sophisticated methods of resisting predators and disease.  Such research is fascinating in its own right, but Angier identified an ethical lesson in it as well, namely, that choosing to be a vegan is morally no better than choosing to be an omnivore.  The claim is both spurious and telling.

Here is the argument:  Because plants escape predators in a sophisticated manner, it follows that they "like to live too," just as animals want to live.  If plants want to live, then it follows that killing them is just as immoral as killing animals.  Vegans fund the killing of plants, while omnivores (and vegetarians, I would add) fund the killing of animals.  Therefore, we are all equally unethical in our consumption habits, according to Angier, and no one can claim the moral high ground.

Angier herself chooses not to eat pigs, she tells us, because she learned that pigs' teeth most resemble human teeth, but she does eat chickens, ducks, fishes, and other animal products.  If her choice is arbitrary -- which she does not deny -- so, then, is the plant-eater's, she argues.

As is often the case in responding to the "gotcha" arguments of defensive omnivores, it is difficult to know where to begin.  To suggest that plants want to live because they have sophisticated chemical means of survival is to attribute consciousness to plants.  Only a being who has subjective experiences like plain and pleasure can want something.  It is, moreover, precisely a being's subjectivity or consciousness that  makes it immoral for us to cause harm to that being.

The fact that plants are well-designed to survive does not make them conscious beings -- "someone" rather than "something."  Most people understand this proposition at a basic level -- if we see a person stabbing a cow and hoisting her upside down as she howls and struggles with wide eyes, we feel sympathy and sadness for her (or we would if slaughterhouses were not so well-hidden from view).  We know that causing such suffering and taking away a conscious being's life is a harm to that being, even as we invent sophisticated justifications for the misery that we inflict.  If we see someone picking a carrot from the ground, by contrast, we do not experience a similar sympathy and sadness.

Perhaps Angier would argue that the new plant research proves that plants truly are conscious.  Otherwise, how could a plant successfully detect the eggs of a predator and produce chemicals to destroy the eggs or summon a super-predator to devour them?

The answer may be found if we consider our own immune systems.  When a harmful micro-organism enters our bodies, if we are healthy, we produce a very sophisticated cascade of immune responses.  We make astonishingly specific antibodies that target the invading micro-organisms and, if successful, devour the threat and prepare for fighting off similar threats in the future.  When this complex process take place, if it is effective, we have no sensory awareness of it at all.  We do not hear, see, smell, taste, or touch either the invader or the defender.  It all goes on outside of our consciousness.  If plants can assemble similarly sophisticated immune responses -- as it appears from the new research that they can -- there is no more reason to think that plants are therefore conscious than there is to think that our own immune systems' resistance to pathogens evidences or reflect our consciousness.

Let us assume, however, in spite of plants' lack of a brain or nervous system, that Angier is truly convinced now that when she eats a potato, she thereby contributes to the suffering of the potato plant.  Does she conclude from this that she should therefore strive to eat fewer plants?  No.  Her important moral conclusion is that vegans are hypocrites, because we murder plants, even as we criticize her for murdering animals (other than pigs, whose teeth are just like ours, and other mammals).

Apart from the immaturity of such an argument, it is also wrong, even on its own terms.  If we believe that plants suffer, then it is our obligation to minimize that suffering.  By eating farmed animals we instead maximize it many-fold, in addition to hurting animals.  Breeding animals requires that we grow plants to feed those animals.  Indeed, an overwhelming majority of the grains and other plants we currently grow in the U.S. is fed to the many billions of land animals we kill every year for consumption.  If we consumed the grain directly and stopped breeding animals, we would spare the lives of most of the plants now "slaughtered."  (And we would engage in billions of fewer killings-per-year of sentient animals as well).  Stated differently, eating animals kills many more plants than eating plants does.

I suspect that this undeniable truth about animal consumption will not move Angier to become a vegan for the plants.  This is because such arguments for the dignity of plants are not generally made in good faith.  Their objective is to mollify the conscience of those who articulate them and to persuade themselves and others that the killing and torment of sentient and aware beings by humans is unavoidable and therefore legitimate.  A clear-eyed look at the facts, however, says otherwise.