Before I forget, I have to say a word about “The Intelligent Plant.” That’s the name of an article by Michael Pollan in The New Yorker late last fall. It’s a fascinating article, which makes one central point – plants are either thinking or doing something unnervingly like thinking. Not everyone agrees with this point: those who do created an organization called the "Society of Plant Neurobiology" in 2005, but the word "neurobiology" applied to plants was so controversial that the group later renamed itself the "Society for Plant Signaling and Behavior." What seems beyond doubt is that plants have an elaborate sensory apparatus, and it’s not limited to impersonal data like soil composition: “Roots can tell whether nearby roots are self or other and, if other, kin or stranger.” With kin, in one research instance, the plants “restrained their usual competitive behaviors and shared resources.” Most vividly, Pollan describes time-lapse video of a bean plant looking very much as if it is deliberately heading for a particular bar up which it will climb; when it gets there, “the plant appears to relax; its clenched leaves begin to flutter mildly.”
Not to belabor the obvious, but it is troubling to think that one is eating what had been a thinking and feeling creature. I cope with this uncomfortable thought while eating meat, but now it seems possible the same guilt attaches to eating plants. Even vegetarians may be killers.
Perhaps we shouldn’t worry, because apparently none of the scientists studying plant cognition assert that plants have emotions, but I’m not at all sure why we should be confident they don’t have emotions, if we ultimately believe they somehow make choices based on data. Emotions help humans make choices; wouldn't they likely be helpful to plants for the same reason? And if cognition can somehow take place without a brain (or at least without a brain-equivalent that's yet been identified), why not emotions too?
If the no-emotions argument is unsatisfying, can we get off the ethical hook because, as one scientist told Pollan, “Plants evolved to be eaten—it is part of their evolutionary strategy”? I don’t think so; Pollan quotes another scientist saying plants may feel pain, and it seems to me that an individual plant may be sorry to give up this life, no matter how much its doing so contributes to its evolutionary strategy. Human beings don’t welcome death, after all, even though that’s certainly part of our biological nature.
The world we are fortunate to inhabit is full of life, life of all sorts, life everywhere. But this profusion of creation seems to rely on mutual slaughter to continue.