Conversation between a biologist and a philosopher: self, transformation and religion (1)

« La danseuse de cordes s'accompagne avec ses ombres », by Man Ray (1916). Haka004/Flickr

Two professors from the University of Lorraine discuss questions of the self, non-self and religion. A biologist begins and a philosopher responds.


Proposition of Jean-Pierre Jacquot, professor of biology

The only time you study philosophy in the French high-school system is in the last year, when you’re 17 or 18 years old. My philosophy teacher was a nice man though with a peculiar characteristic: he possessed very large ears, a trait we students discussed with much interest – we didn’t yet know that ears grow continuously with age and he was in fact quite old already. For those interested in science, philosophy was hardly a major subject, and we were listening with only one ear (and a small one as we were still pretty young). On top of that this professor spoke in a very flat tone that was hardly entertaining.

There was one day, however, when he fully attracted our attention and that was when he started discussing the self and the non-self. I vividly remember the example he chose and can almost repeat it word for word nearly 45 years later. He said the following: “When I go to the toilet, what has been eliminated was me a few seconds ago. But all of a sudden it has become a non-me. But in fact this non-me was me just a little while ago and at the time I did not consider it as a non-me”.


Perceptions of the self and non-self

We were actually stunned by this line of thinking because it rings true and neatly explains the difference we make between the self and the non-self – generally the self is perceived as good, the non-self as bad or threatening. Much later life, I was retelling this lesson of philosophy to some colleagues at a dinner and one of them insisted at defining himself as my non-self, so I was not sure whether he had really understood the concept… Given his wonderful sense of humor, I believe that it’s a bit self-deprecating. As a courtesy, I define myself as his non-self…

So what does biology tell us about the self and the non-self and how does this lead to considerations about religion and metempsychosis (the Greek concept of the transmigration of the soul)? Well, I have been doing research in photosynthesis for more than 40 years, in particular the fixation of carbon dioxide, and for nearly 20 years plant biology and biochemistry. My teaching deals essentially with photosynthesis in chloroplasts and respiration in either plant or animal mitochondria. To put it simply, in photosynthesis, plants combine carbon dioxide and water to form carbohydrates and oxygen and conversely in respiration carbohydrates are degraded with the help of oxygen to yield carbon dioxide and water. The two reactions run in opposite directions using the same reactants/products as described in the equations below.

Author provided

These biochemical considerations lead to the following observation: when I breathe next to a plant doing photosynthesis, I consume the oxygen liberated by this plant and release carbon dioxide which is then assimilated by the plant. It follows that the carbon dioxide that was me a while ago has now become part of the plant and conversely the oxygen that the plant liberated has been integrated in my body. If I talk in terms of self and non-self, part of what is now the plant was me a few seconds ago and vice-versa. Simple but also stunning isn’t it? The argument can be extended to all nutrition: if I am eating fish or meat or carrots or bread, what was a salmon, a cow, a carrot or wheat has become me. On the other hand, after I have made the necessary adjustments that my metabolism requires, these components that were me can now be taken up as nutrients by plants and bacteria. (And indeed, haven’t we used animal manure in the fields as fertilizer for millennia?)


We are only concepts

These simple considerations lead to the following understanding: although animals, micro-organisms and plants look like entities, in reality we do not exist as such. Instead, we are constantly exchanging ourselves with the external environment through the nutrient cycles. It follows that the self and the non-self are actually shaky concepts, as my philosophy teacher rightly guessed. In some ways we are just concepts ourselves. Had I been less interested in girls in high school I might possibly remember which Greek philosopher suggested that the world is a mere illusion. Somehow it makes sense on a biological standpoint. In a Joni Mitchell song there is a verse that goes “We are stardust, we are golden…”. Golden, I’m not sure, but stardust certainly – we are all stardust continuously exchanging with our environment, be it your neighbors, the plants next to you or the microorganisms within you, on your skin or inside your body. As a matter of fact, in a human body there are apparently more microbial cells than eukaryotic cells, the majority of which are located in the gut…

Where does lead in terms of metempsychosis and religion? Metempsychosis is a belief that a soul can exchange bodies, that after death you can retransform yourself into a completely different human being, animal or even plant. I don’t know if souls exist but biology tells me that indeed we transform ourselves constantly into plants and micro-organisms in way that are similar to metempsychosis. Apparently in eastern beliefs metempsychosis does not necessarily require the notion of a soul, but we could possibly transform the word metempsychosis into metempsomasis, the soma being more or less the bodily part of a human being. In this sense, yes, I believe in metempsychosis.

Sean/Flickr, CC BY-ND

What about religion? Isn’t the most reassuring aspect to comfort people about their impending death and the promise of an eternal life for their soul? What biology tells me about death is that it will be the ultimate reinvention of myself. All my life I will have exchanged myself with my environment, and after death my atoms and molecules will be used to create new life. Isn’t that comforting enough? Aren’t we all immortal in that way? Do we really need a God to reassure us? For some people the answer is yes, for others the thought of being fully recycled in afterlife may be sufficient to calm any anxieties.

The take-home message could be as follows: My friends, after what is the illusion of me dies don’t be sad. I will be always be around you in the trees, the flowers, the meadows, the cows, the birds and parts will even be inside you, literally. No need to panic there.


The response of Roger Pouivet, professor of philosophy

Let us summarize the argument of Jean-Pierre Jacquot. Through their metabolism, living organisms assimilate parts of their environment and conversely release parts of themselves into their surroundings. As a consequence, a living organism integrates something it was not and becomes something else. “If I eat fish or meat or carrots or bread, what was a while ago a salmon, a cow, a carrot or wheat has now become me.” And, “After I have made the necessary adjustments that my metabolism requires, these components that were me a while ago will quickly be re-assimilated by bacteria and plants.”

Hence “Although animals, micro-organisms and plants look like entities, in reality we do not exist as such. Instead, we are constantly exchanging ourselves with the external environment through the nutrient cycles.” From biological facts, Jean-Pierre Jacquot draws conclusions about the self in philosophy. Hence, given that we do not exist as well defined entities (contrary to the appearances), survival after death would only be a comforting illusion. Interpreting these biological data would then lead to a beautiful lesson of philosophy concerning what we are and the pretenses of the religions.

However, it is an argument I do not find convincing, and I am especially skeptical about drawing the existential consequences that Jean-Pierre Jacquot suggests.

That a biological organism assimilates elements of his environment and discards the refuse is a banal observation that biology can easily formulate and describe. Do we need to infer from that that there are no living beings with stable identity? The response is positive if an organism cannot change while remaining a “self”. However, why would that be impossible or even unlikely? If a rabbit fattens or starves it remain a rabbit. Not only does it remain a rabbit, it remain a specific rabbit – let’s name him Roger Rabbit for the sake of argument. Whether he has eaten a carrot or not does not make Roger something other than what he was. He will remain a rabbit and more specifically Roger Rabbit until he dies of natural causes or eaten by a rabbitophile.

Even the complete cell renewal of a living being, especially gradual, does not result in the loss of one’s identity. Metabolism, in opposition to what Jean-Pierre Jacquot suggests, can be interpreted as an index of the ontological stability of living beings rather than of their evanescent nature.

How about the self/soul? Is that an illusion? It has often been identified with consciousness. It would be the soul and not the body that would ensure the permanence of a human being through time and space. Some dualists believe that the soul or perhaps the memory could survive a body change. Jean-Pierre Jacquot discussion is based on the memory of a philosophy lesson he experienced long ago. This is his memory, not the one of a human being that he is no longer. Taking a course requires some mental continuity (although he seems to have had problems concentrating, from what I understand…). In opposition to his thesis, what he is writing clearly indicates that he indeed possess a personal identity, something I doubt that he doubts.

Jean-Pierre Jacquot also tells us that pieces of himself will be scattered in things after his life. If the identity through time is an illusion, would pieces of himself trail after? However, I will not attempt to defend the thesis that the identity of a person is only linked to his thinking-self, as developed by John Locke in the 17th century. Just as changing a rear-view mirror does not result in a new car or making a stain on a piece of cloth does not create a new piece cloth, the carrot-lover will remain the same even after eating one or several. We live an “existensial” life in some ways, from our birth or even before until our death. And perhaps even beyond, although I admit that not everybody agrees with that.

Can a living being remain identical while at the same time evolving? To answer that question, one must analyse what a living being is and what remaining identical is. Also does a living being possess in itself something establishing its identity? Is a living being entirely present throughout its temporal evolution? Or else, is a living being actually scattered in time? Does survival after death concern only the soul and then the body would be accessory or even unnecessary? These are clearly metaphysical questions and it would certainly be desirable to treat them in a multidisciplinary teaching program.

This article was originally published in French

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