The Biology Of Suffering

“Where does suffering come from? Why do we suffer?”

These questions open biologist Ursula Goodenough’s essay “The Biological Antecedents of Human Suffering” (in The Routledge Companion to Religion and Science (2012)). We’ve looked to religion for answers, with no easy satisfaction. Under a wise biologist’s eye, the questions look quite different.

Goodenough proposes two categories of suffering, biological suffering and experienced suffering. Biological suffering is common to all living things. Bacteria, plants, and people all draw towards what they need—water, food, light—and away from what will harm them—toxins, dangers, enemies. Too little of what an organism needs or too much of what will hurt it will leave it struggling.

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The Four Horsemen of the Apocalypse by Albrecht Dürer  (

For animals with developed nervous systems, however, such suffering not only takes place biologically but is also experienced. The biological difficulty announces itself through the nervous system. Vertebrates in particular carry neurons called nociceptors in the skin and internally in muscles, joints, and the gut. Nociceptors transmit to the brain the message that something is very wrong, a message the brain interprets as pain—a finger sliced with a knife,  a twisted ankle, sudden nausea. And for humans—social and self-aware creatures that we are—the sources of experienced pain include social (envy, loneliness) or psychological (guilt) feelings as well as bodily injury.

Fortunately, for most of the difficulties that organisms endure, there are antidotes. Organisms will move towards water if they need it, try to compensate for an injury, muster immune responses to fight infections, call a friend if they are lonely. Goodenough calls these corrective measures amelioration systems; they make things better.

Amelioration systems come in many forms. Often, and not always pleasantly, we humans can feel them at work more sharply than the adversity that triggered them in the first place. Our noses get stuffed up during a cold not by the rhinovirus but because our immune system swells the sinus blood vessels in order to muster antibodies against the virus. Similarly, we run a fever not directly because of an infection but because a higher body temperature strengthens the immune response.

To paraphrase Goodenough, organisms whose amelioration systems fail to cope with adversity will die. Organisms whose amelioration systems are inactive because they have all they need enjoy well-being. But it is organisms whose amelioration systems are at work “actively dealing with difficult circumstances” that are in a state of biological suffering.

So all organisms suffer. Sometimes the suffering is not felt: “The food-deprived amoeba or the bacterium, the plant plunged in darkness or subject to a wound, pays the suffering price, but does not feel the price.” In other cases, for humans and other vertebrates, the price is felt as acute pain. Such pain by itself doesn’t ameliorate a condition but calls attention to it—and may teach a lesson about what to do differently next time.

But in still other cases, recurring or continuous pain is a scam. Chronic pain is “physical pain that is not obviously in the service of amelioration systems and is unresponsive to analgesics or other practices….Here we encounter an example of things gone awry.” With chronic pain, “Suffering has become uncoupled from resolution.”

In closing, Goodenough writes, “The long evolutionary view of suffering is that it is an inherent feature of life….[It] is part of the package, the price paid for the gift of being alive at all.”

Up to a point, we knew this already—that some suffering goes with being alive. But Goodenough’s naturalist perspective is knowledge of suffering in a different mode, with less mystery, less guilt, and perhaps easier acceptance. And it’s an irony appropriate to the complexity of life: that so much of what we suffer from are the symptoms of the work of repair and renewal.

These highlights amount to only a partial summary of Goodenough’s rich essay. Interested readers will find the original here at Google Books.


The Limits of Happiness?

If our expectations of happiness sometimes seem off-kilter, it’s because our understanding of emotions in general is not always accurate. It is tempting to think that emotions are available in pairs, that each pleasant emotion comes with a distressing version: happiness matched with sadness, bravery with fear, contentment with  frustration. And we might expect that people experience emotions in a wide range of intensities and durations. Depending on the person, sadness might last for a day or a decade, mildly or intensely. And and so might its counterpart, happiness.  As the sign says, “Happiness has no limits.”

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In How the Mind Works, Stephen Pinker says not so fast. For starters, “There are twice as many negative emotions (fear, grief, anxiety, and so on) as positive ones.” Try to count the common unpleasant emotions that come to mind, then try to think of the same number of positive ones.

Another clue that emotions don’t come in positive and negative pairs in all varieties, like shoes, is that “[P]eople’s mood plummets more when imagining a loss in their lives (for example, in course grades, or in relationships with the opposite sex) than it rises when imagining an equivalent gain.” Pinker quotes tennis star Jimmy Connors: “I hate to lose more than I like to win.”

So not only are negative feelings more plentiful than positive ones, but they pack a stronger punch as well.

Why? The benefits of happiness and the other positive feelings are, in evolutionary terms, more limited than we might think. Pinker: “The psychologist Timothy Ketelaar notes that happiness tracks the effect of resources on biological fitness. As things get better, increases in fitness show diminishing returns: more food is better, but only up to a point. But as things get worse, decreases in fitness can take you out of the game: not enough food, and you’re dead” (392).

So the dangers of of injury, illness, and enemies call for variable levels of distress to signal the seriousness of the threat—emotional smoke alarms that can grow louder and last longer as the threat intensifies. But the joys of health, sociability, creativity, and even spirituality don’t call for such intensification. In the long run, we wouldn’t gain from a capacity for increasingly intense joy or confidence or satisfaction or excitement. Too much joy for too long and we let our guard down.

So we care more about what could go wrong than about what could go better.


No Pain, No Sympathy

Which living things merit our sympathy? Our pets? Certainly. What about human embryos? And plants? Is it consciousness or complexity or being human or the capacity for pain that makes an individual life worth our empathy?

The debate over animal rights has reinforced one ancient measure of an organism’s worth. An organism that shows signs of experiencing pain is said to be entitled to live without that pain. These sentient beings include cats and dogs and most of the animals that we eat or use for clothing or experiment on. Insects, with their minimal nervous systems, are on the margin of the sentience line.

Below the line are the simplest animals such as sponges and jellyfish, along with plants and single-celled bacteria and other microbes. These don’t experience suffering and have no awareness of a kind that we would recognize. They may have value collectively as part of the environment, but a single jellyfish or an individual plant has no standing for human commiseration.

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Although I understand its role in the cause of animal rights, I find this sentience distinction unsatisfying. If an organism appears to be “feeling” a disease or injury, we give its condition more weight and urgency than we would if the organism—a plant, for example—were one that did not consciously experience such a condition. A tree may be attacked by insects or suffer other life-threatening conditions, but if we are accustomed to imagining the terror of a pig going to slaughter, we probably won’t empathize much with the stress on the tree as chemical messages sweep through it.

When we feel compassion for another being that is in dire straits, what are we feeling sympathy for, exactly? Is it for the possible loss of an individual life? Is it for the dangerous condition that is attacking the organism? Or is it for the pain that the organism is enduring? I think it is the last, if only because the evident pain in an animal reminds us of our own capacity for suffereing. Perhaps we should remind ourselves that non-sentient beings, though without visible torment, may struggle, crave, and weaken as relentlessly as sentient ones.

The uniqueness and persistence of life over 3.8 billion years endows all living things, both with and without awareness, with value. I’m not recommending the ludicrous extreme of not killing plants; we, like all animals, can not survive without eating other living things, either plant or animal. But I am suggesting that we heighten our awareness of the sentience distinction that cleaves the living world in two and can diminish our connection with non-sentient life.