Are plants sentient beings?

An article in the Guardian reviews a new book Brilliant Green that asks "Are plants sentient?"  I answer with a general yes. Obviously the entire range of flora have different degrees of sentience just as the entire range of fauna have differing degrees of sentience. The wide meaning of sentience means feeling-perception-awareness, e.g., any kind of sense of environment, and the narrow meaning is self-conscious or intelligence measured by self-consciousness.

With the wider meaning, all living beings have some degree of sentience, i.e., awareness. Otherwise they would not be living beings. Traditionally, with the earlier and less sophisticated narrower views of sentience, only people were considered sentient beings having our kind of self-consciousness as our definition of intelligence, and animals and plants were not considered sentient. No recognizable self-consciousness meant no consciousness and therefore no sentience or intelligence.   However, life means interaction, relationship, stimulus and response, so I include all living beings in the category set of sentient beings because responding to the environment, no matter how simplistic or limited, is the sign of "feeling" and the presence of awareness and is thus being active in the response to the environment. Therefore to me, all living beings are sentient.

Next is the question of the degree of sentience. Obviously, there is a spectrum of sentience with mammals at one end and perhaps mold or plankton at the other end. Here, I think the question of self-consciousness is relevant. While all sentient beings are sentient, not all are self-conscious to the same degree.  However we have to watch for species-centric bias because as mammals, we humans can't even access the ranges of sentience on the sensory spectrum that some other mammals can. For example, we can't hear the range of sound that a dog or dolphins can. So there may be many areas of the field of sentience that we are unaware of. An open grass prairie and a redwood forest have different feelings to them for us, and these different feelings arise from them, not just our imagination. The different feelings that we are sensing are our limited perception of the sentient fields of those different plant communities.

In Buddhism, there is the concept of Buddha fields or Buddha lands which are of infinite variety and relate to all the fields of sentience of all the sentient beings. In addition to Buddha lands being other dimensions or other planets or galaxies, they are also other being's fields of consciousness, such as the Elephants' Buddha land where beings can communicate with stomping on the earth or dolphins' Buddha land where beings communicate by whistling, clicking, sounds.

When trying to assess a degree of sentience in terms of self-consciousness, the Buddhist model of the 5 Skandhas is helpful. All living beings have the activity of all five skandhas, (1) sensory data, (2) feeling-reception of senses, (3) perception (4) complex activity for identifying and responding to the perception, and (5) consciousness.    It is the degree of the complexity of the fourth skandha's unconscious formations and complexes that conditions the degree of self-consciousness of the fifth skandha. From our human perspective, ants, bees, and other hive creatures appear to lack an individual self-consciousness as we would understand it, yet we perceive what appears to be some kind of group- or hive-mind self-consciousness.

Again, we are high up on the predatory food chain and have "conquered" the planet according to our own species-centric assessment, yet there is much we do not understand about other creatures, both animals and plants, and when we destroy our own ability to live on the planet by pollution, climate change, or nuclear war or power radiation, there are other species of sentient beings who will survive, and then from their perspective they will be the meek who have inherited the earth.