Showing posts with label consciousness. Show all posts
Showing posts with label consciousness. Show all posts

Thursday, April 20, 2023

Do Plants Think?

A relatively recent (2021) article on plant intelligence, which includes an interview with Monica Gagliano, a professor in Evolutionary Ecology at Southern Cross University in Australia:

Plant Intelligence

It's known that plants can communicate with each other to "warn" their neighbors about potential attacks. Some plants also use animals to defend against pests, such as by releasing chemicals to attract wasps that prey on caterpillars. Researchers have discovered evidence that plants may have "memory" of a sort. In the interview, Gagliano defines intelligence as decision-making in reaction to one's environment. She insists that "you do not need a nervous system or a brain to embody this kind of behaviour and decisions." She goes so far as to declare, "Of course plants are intelligent, as much as bacteria and amoebas, and fish and birds and humans."

Bacteria? That wide-ranging application of the concept may come as a shock to many people's mental categories, as it does to mine. We typically think of intelligence as requiring brains and involving sapience or at least consciousness. I'm reminded of a vintage horror story that begins with a conversation about the nature of mind, in which one character rhetorically asks, "With what does a plant think, in the absence of a brain?" The other character scoffs, while the first maintains that intelligence exists everywhere in many shapes. When or if we eventually travel to extrasolar planets, we might plausibly discover plants or a vegetative group mind possessing a capacity for thought we'd recognize as similar to our own. However, mutual communication might be hard because organisms the size of trees or larger might think on a slower time scale than we do—like Tolkien's Ents, only much more so.

Another article on plant intelligence I came across queried whether, if plants can think in some sense, we would be obligated to stop eating them. If so, we'd be stuck with rather narrow diets, composed entirely of foods we could harvest without killing any complex organism (dairy products, unfertilized eggs, fruits, nuts, honey, the leaves of green vegetables that regenerate throughout the growing season—that's about it). Fortunately, the writer of that essay reassured us we wouldn't, since animals regularly consume plants as part of the cycle of life. Besides, many plants have parts (e.g., fruit) especially meant to be eaten by animals for the purpose of spreading seeds.

Remember the Shmoos in the old "Li'l Abner" comic strip, delicious animals that rejoiced in sacrificing themselves as food?

Shmoo

Maybe on a world shared by intelligent plants and humanoids, some vegetative life forms would partake in a symbiotic partnership whereby they produced renewable offshoots to feed sapient animals in exchange for helpful services such as fertilizing and pest control.

Margaret L. Carter

Carter's Crypt

Thursday, October 27, 2022

Is Time Travel Impossible?

A character in C. S. Lewis's posthumously published novel fragment THE DARK TOWER asserts it is. (Granted, one faction within Lewis scholarship maintains THE DARK TOWER wasn't actually written by him, but I don't find that claim convincing. Anyway, the issue doesn't affect the point of the story.) He argues that physical travel to the past or future can't be done for a basic, irrefutable reason: A corporeal trip into a different time necessarily carries all the atoms in one's own body into that other time. But in the past, all those particles existed in other entities in the physical world, whether inanimate objects, living creatures, liquids, gasses, whatever. In the future, those same particles will again be distributed through the environment. The only way you could materialize in a different moment would be if duplicates of each of your atoms, molecules, etc. existed in the same place at the same time. According to the laws of physics as we know them, that's impossible. Therefore, physical time travel is forever, irrevocably ruled out, unless we invoke magic rather than science.

That story is the only place where I've encountered this argument, which strikes me as highly convincing. On this hypothesis, other temporal "locations" could be only viewed, never visited. Accordingly, Lewis's character has invented a device for viewing other times, although it turns out the true situation is more complicated than he believed.

While I've come across other stories of observing rather than traveling to some non-present time, I don't remember any that offer a theoretical grounding for the impossibility of temporal travel in the flesh. It's not unusual in time-travel fiction, however, for a traveler to be unable to exist in the same location more than once in the same moment. In Dean Koontz's LIGHTNING, a traveler can't visit a place/time where he already is/was. He's automatically shunted away from that point. In Connie Willis's series about time-traveling historians from a near-future Oxford University, the same prohibition applies, but it's not clear whether the simultaneous existence of two of the same person is outright impossible or would produce a catastrophic result if it accidentally happened. In such works as the Harry Potter series, THE TIME TRAVELER'S WIFE, and Robert Heinlein's "By His Bootstraps," on the other hand, any number of you can be in the same point in space/time at once.

To me, the former rule seems more plausible, because it makes the issue of the same material object being in two places at once less obvious, although I've enjoyed lots of fiction in the second category. One possible way to get around the problem raised in Lewis's DARK TOWER: Instead of a corporeal leap into a different time, travelers might project their consciousness and build temporary bodies in the other time by "borrowing" stray particles from the surrounding air, water, and earth. When the traveler released the borrowed matter to return to his or her point of origin, the particles would dissipate harmlessly into the environment. Another method of bypassing the problem shows up in the new QUANTUM LEAP series: The leaper's consciousness occupies the body of a person in the past, presumably suppressing the host's personality in a sort of temporary, benign possession. (The time-shift operated differently in the original series, while this version does leave unanswered the question of where the leaper's body is while his immaterial consciousness travels to multiple past eras.)

Margaret L. Carter

Carter's Crypt

Thursday, June 23, 2022

Is Consciousness an Illusion?

A famous psychological experiment in the 1980s seemed to prove that the brain "decides" to take actions before the conscious mind makes the choice to do so, and the decision we think we're making is only a rationalization after the fact:

Scientists Still Haven't Figured Out Free Will

Many experts in the field have reservations about this "proof" and have pointed out flaws in that interpretation of the results. A Wikipedia article goes into great detail about this experiment and other aspects of the "free will" issue in psychology:

The Neuroscience of Free Will

There's also a psychological theory that the "self" we think we have or are is an illusion, a trick the brain plays on itself. For one thing, our concept of our own identity arises from continuity of memory, an imperfect process riddled with gaps and reconstructions.

Here's one analysis of that issue:

The Illusion of the Self

The author of this article, Sam Wolfe, summarizes cognitive scientist Bruce Hood's thesis that our "selves are generated by our brain in order to make sense of our thoughts and the outside world: both ‘I’ and ‘me’ can be thought of as a narrative or a way to connect our experiences together so that we can behave in an biologically advantageous way in the world." Wolfe endorses this position and cites support for it dating back many centuries, to 18th-century philosopher David Hume and, much further, as a traditional tenet of Buddhism. What we think of as our "self" arises from the brain as a "narrative-creating machine." As Wolfe puts it, "Essentially, our brains are always thinking in terms of stories: what the main character is doing, who they are speaking to, and where the beginning, middle, and end is; and our self is a fabrication which emerges out of the story-telling powers of our brain."

I wholeheartedly agree that the creation of stories is an essential aspect of the human brain, part of what makes us human. I can't agree with people such as Bruce Hood and Sam Wolfe, however, on their insistence that the narrative of a unified self doesn't correspond to reality. We visualize the self as a little cartoon person at a control panel somewhere in our head, directing the subordinate brain functions, or maybe, as in the animated film INSIDE OUT, a small committee of persons in a control center making executive decisions. Only a metaphor, of course, but regarding the singular self as an illusion seems to generate an intractable problem.

Since, as Hood and Wolfe acknowledge, "everyone experiences a sense of self – a feeling that we have an identity," if this sense of self is an illusion, a construct the brain creates to enable us to function in everyday life, who is the "us" believing the illusion? This theory seems to lead to an infinite regress of "selves" being fooled. Also, it seems to me a not-insignificant objection that it's impossible in practice to live as if one believes no actual self exists, or not for long anyway. And, again, who's doing the believing?

Margaret L. Carter

Carter's Crypt

Thursday, September 24, 2020

Self-Aware Cells?

The September-October issue of SKEPTICAL INQUIRER reviewed a book called THE FIRST MINDS: CATERPILLARS, 'KARYOTES, AND CONSCIOUSNESS, by Arthur S. Reber. Although I haven't read the book, only the long, detailed review essay, it sounds intriguing. Reber addresses the "problem of consciousness"—how did it originate from non-sentient matter? how is this seemingly immaterial phenomenon related to the material body?—from the simplest organisms up. He proposes that even single-celled organisms have agency, subjectivity, and sentience. He maintains that from the beginning of evolution, even the most "primitive" life-form must have been "sensitive to its immediate surroundings and to its own internal states." The review paraphrases his view as asserting that "to understand consciousness we must look first at the single-celled organism rather than. . . the human brain."

But sentience is customarily distinguished from "perception and thought." Does Reber claim that a one-celled life-form is self-aware, our usual meaning of "conscious"? The reviewer asks, "Is Reber really asserting that a unicellular organism has a mind?" Apparently so. Reber also seems to assume that amoebae can feel pain. What about plants? Reber remains agnostic on this question, pointing out that sentience wouldn't bestow any clear evolutionary advantage on a creature that can't move. As time-lapse nature photography demonstrates, though, many plants do move, just too slowly for us to notice in real time. (Some of the "weed" bushes in our yard, I think, do grow almost fast enough to be observed by the naked eye.)

Going even further, he suggests that the individual cells in our bodies are not simply alive but sentient. The reviewer asks, "Do we harbor an entire universe of minds?" Reber would answer in the affirmative, again apparently defining "mind" and "consciousness" very broadly. This concept reminds me of Madeleine L'Engle's A WIND IN THE DOOR, in which the characters become infinitestimally small to enter the body of Meg's critically ill little brother, Charles Wallace. They meet a community of farandolae, sub-microscopic creatures dwelling inside the mitochondria within one of Charles Wallace's cells. To a farandola, cells are worlds, and Charles Wallace's body is a galaxy. Much more recently, an ongoing manga series currently in print, CELLS AT WORK, portrays the internal organs and processes of the human body from the viewpoints of blood cells and other cells, each an individual character. Presently, the protagonist red and white cells have been involuntarily moved, by transfusion, from their original body to a new one. They have to cope with new (and worse) working conditions and learn to cooperate with the body's veteran cells. This is a fun, fascinating series, conveying biological facts in an informative and entertaining way, as accurately as possible considering the premise of humanoid, intelligent cells, who seem to survive a lot longer than white and red blood cells actually live.

The reviewer in SKEPTICAL INQUIRER discusses the obvious problem with Reber's hypothesis, that a blood cell or an amoeba is obviously not a human brain, and the emergence of the more complex structures and functions can't be equated with or explained by their simpler predecessors. According to the article, Reber doesn't manage to solve the problem of mind, which has baffled philosophers and scientists for millennia, but the reviewer still recommends his book as "a worthwhile contribution to the literature on consciousness."

The notion of conscious or even sentient cells is intriguing to contemplate but, if accepted with full seriousness, would paralyze our ability to carry on with daily life. Could we kill disease germs or even surgically excise cancers? If a tumor were self-aware, would it consider its right to life preempted by ours? The mind boggles.

Margaret L. Carter

Carter's Crypt

Thursday, August 17, 2017

Undersea Aliens

Peter Godfrey-Smith, a professor at the University of Sydney and City University of New York, believes the octopus is the closest thing to an alien living on Earth with us. Octopuses "are the most complex animal with the most distant common ancestor to humans."

Octopus Intelligence

In many ways, octopuses seem as different from us as an advanced creature can be and evolve on the same planet. They have three hearts and blue, copper-based blood. They have the ability to change color, which they use for camouflage. Suppose we encountered an extraterrestrial species of intelligent cephalopods who communicated by waves of colors? We would have to learn a whole new mode of language. Octopuses "developed eyes, limbs, and brains via a completely separate route" from us. With neurons distributed through their bodies instead of solely localized in their heads, we might say they have brains in their arms. They show considerable intelligence, such as in escaping from confinement, and they can tell human individuals apart. Octopuses seem to play, another sign of high intelligence. They also display curiosity, which Godfrey-Smith thinks may be evidence of subjective consciousness. If so, consciousness has appeared separately at least twice on Earth.

It has been suggested that a possible reason why they haven't evolved even higher intelligence springs from their reproductive cycle. Male octopuses typically die soon after mating, and females don't live long past the hatching of their offspring. Therefore, adults don't survive to pass on knowledge and skills to their young. Octopuses can't have much of a culture, if any. Their solitary lifestyle (aside from mating) is probably another factor, since gregarious species tend to be more intelligent than solitary ones; interactions with other members of one's species in a group require mental flexibility.

Godfrey-Smith makes the optimistic assumption that the evolution of consciousness at least twice on Earth implies consciousness isn't a rare fluke, but a potentially common natural development. That assumption, if valid, bodes well for the discovery of sapient beings elsewhere in the universe. If a race of giant octopuses on another planet—perhaps one mainly or entirely covered by water—overcame the disadvantages of their short, solitary lives, maybe by evolving a long-lived, asexual caste responsible for the care and education of the young, they could create something we would recognize as a culture.

Margaret L. Carter

Carter's Crypt

Thursday, July 14, 2016

Insect Consciousness?

A honeybee scientist, Andrew Barron, and a philosopher, Colin Klein, have collaborated on a study that suggests insects may have consciousness and emotions:

Insects Are Conscious

Does insects' inner life comprise more than simple reflexes? Conventionally, the neocortex is thought to be the site of consciousness. Suppose, rather, the "much more primitive midbrain" synthesizes experience into "a unified, egocentric point of view"? Barron and Klein maintain that insects have midbrain-like neural structures that enable them to "model themselves as they move through space." (The quotations come from an article about this study in SMITHSONIAN magazine.) Insects may feel, at the very least, hunger and pain.

Since I've always shared the prevailing belief that invertebrates don't have enough neural processing capacity to feel anything, this hypothesis strikes me as rather unsettling. Insects do appear to "plan," in a sense, in that they pursue definite goals. They can learn from experience (even flatworms, a much "lower" life form, can do that), so do they have "memory"? They make choices between alternatives, so are they "deciding"?

Whether insects have consciousness and the ability to think depends, of course, on how we define "conscious" and "think." C. S. Lewis in THE PROBLEM OF PAIN points out that an unconscious human body may reflexively react to hurtful stimuli although obviously without being aware of pain. If by "self-awareness" we mean the ability to meditate on our own existence, possibly only human beings have that quality. Self-awareness on the level of recognizing one's own reflection in a mirror is confined to us, some primates, and a select few other animals. If "thinking" means only abstract thought that can be formulated in words, by definition we classify ourselves as the only thinking organisms on the planet. If any kind of problem-solving equals thinking, the field becomes much wider.

I once read a story (can't remember the title or author) in which one character tries to convince another that thought isn't confined to human beings and higher animals. He says, "With what does a plant think, in the absence of a brain?"—classifying a plant's phototropism as a form of thinking.

Barron and Klein hope investigating the mental lives of insects may throw light on the origins of subjectivity in "higher" species, including ourselves.

Margaret L. Carter

Carter's Crypt