The idea that plants might have feelings is usually greeted with loud guffaws in Western circles. We've smiled tolerantly at the idea of Prince Charles talking to his plants, while the national newspaper cartoonists must have thanked their lucky stars the day the story broke.
The subject always reminds me irresistibly of the scene in the Richard Curtis comedy, Notting Hill, when the Hugh Grant character, William Thacker, is being set up by his friends with a rather earnest girl called Keziah, who tells him she is a fruitarian.
William: And, ahm, what exactly is a fruitarian?
Keziah: We believe that fruits and vegetables have feelings, so we think cooking is cruel. We only eat things that have actually fallen off a tree or bush - that are, in fact, dead already.
William: Right. Right. Interesting stuff. So, these carrots ...
Keziah: Have been murdered.
William: Murdered? Poor carrots. How beastly!
However, a new book by Dr Matthew Hall, of the Centre for Middle Eastern Plants at the Royal Botanic Garden, Edinburgh, seeks to challenge this attitude. It's called Plants as Persons: A Philosophical Botany and it explores the relationships between humans and the plant world.
The proposition, to put it as simply as I can, is that we tend to see the world in zoocentric or anthropocentric terms, which means we do not consider plant life to require the same sort of moral consideration as humans or animals.
Because of this, we are often more destructive and callous in our attitudes to plant life than we might be towards what we consider "higher" forms of life, such as mammals (and goodness knows we are pretty careless about those).
This hierarchical view of the natural world is something that has developed over millennia, both from the ancient Greeks and the teachings of Aristotle, and from the Old Testament, which teaches that man has "dominion" over the world.
"And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth." Genesis, 1:26
Indeed, I have to admit that I am so deeply steeped in this tradition that I personally find it very difficult to get my head around the idea that there may one day be a "plant liberation" movement in the way that we have an "animal liberation" movement.
Dr Hall says: "In the ‘West’ (wherever that is) we don’t include plants within our moral sphere, a situation which most people think is ‘normal’. I basically wrote the book to try and find out why that was our default position, and to see if there were other ways of looking at plants, both from other cultures and from within plant science writings about the 'intelligence' of plants.
"The first three chapters look at this ‘exclusion’ of plants from the moral sphere and my argument is that this exclusion has been a deliberate process aimed at distancing humans from any sense of kinship with plants, something which we did once have.
"This is done by humans deciding that the faculties which humans or animals possess are somehow radically different and better than those plants possess. This has led to the idea that plants are a lesser form of life with lesser faculties, lacking in sensation, movement and intelligence.
"It’s really difficult to say why we’ve done this, but it always seems to be connected with a need to claim the natural world purely as a passive human ‘resource’ (as happens in Plato, Aristotle, the Bible) rather than as an equally valid, and related, place of life and being.
"For me, this process only really became clear when I looked at other cultures where plants are related to as proper persons (as well as being resources) because they are related to humans as creatures that come from the Earth, and because (as anyone who looks closely at plants sees) they obviously actively live their lives. Most interestingly, this way of looking at plants is backed up by lots of recent scientific evidence on plant behaviour."
So which cultures DO regard plants as worthy of the same care and consideration? What about Buddhists?
Dr Hall says: "Interestingly, Buddhism is actually split on whether plants are sentient or not. In Tibetan Buddhism for example, plants are not one of the six realms of sentient life. Tibetan Buddhists can’t be reborn as plants and therefore eating plants doesn’t involve ‘proper’ killing.
"It’s thought that this is a reversal from an earlier position where plants were thought to be sentient, but similar processes of exclusion rendered the situation similar to the one we have in the West.
"However, in East Asian Buddhism (traditions such as Zen), there has been a tradition of regarding plants as sentient, and some thinkers have even regarded them as enlightened(!), because they show the hallmarks of enlightenment e.g. not accruing any karma, wisdom, patience…
"Plants have been regarded as ‘sentient’ in early Hindu texts and very strongly in the Jain tradition. In Indigenous cultures and in Paganism, people tend not to use the word ‘sentient’ but speak of kinship with plants which are actually related to as proper family (for example, my uncle’s uncle is a kurrajong tree – and with all the respect that deserves) and as proper persons. Amazing really!"
Amazing, indeed - it's the sort of subject that leads you on and on into further investigation and inquiry. I'd always thought, for example, that Jainism was a branch of Hinduism until I looked it up. I now realise that despite superficial similarities, they are actually quite different.
I won't pretend to you that this is anything other than an academic book, but I think the ideas in it are fascinating. I know that, for some years, the Catholic church has been moving towards the idea of "stewardship" rather than "dominion" over the natural world, and for many Christians in general, the ethical issues involved in conservation are beginning to supplant the old belief that the planet was ours to do with as we liked.
However, for us to think differently about the world often requires a really radical shift. Dr Hall ruefully admits that a lot of his scientific colleagues "run a mile at even the mention of the word religion".
He himself takes up no particular religious position, merely asking where these beliefs come from and the effects they have had.
So, are you still guffawing? Or are you feeling rather thoughtful? If it's the latter, and you want to find out more, go here