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Fuzzy Logic & Fuzzy Life

May 2002

The following essay on the politically-charged issue of abortion was originally written for my regular Scientific American monthly column, Skeptic, but we decided that it was too political and not grounded enough in science for Scientific American, so we shelved it. I ended up expanding that column into a chapter section in my book The Science of Good and Evil.

In 1959 astronomers were polled for their opinion on the then undecided debate between two competing cosmological theories. “Did the universe begin with a Big Bang several thousand million years ago?” A third answered yes. “Is matter continuously created in space?” Almost half answered yes. Most telling, to the question “Is a poll of this kind helpful to scientific progress?” all answered no.

The reason for this unanimity is that scientific questions are not settled by consensus opinion. Unfortunately, in complex human and social issues, separating fact from opinion is not so easy, and for no issue is this more apparent than abortion. Setting aside the emotionally charged moral and political aspects of abortion for a moment, how can science inform this debate?

At the core of the moral and political question of whether or not aborting a fetus constitutes murder is the scientific question of when a fetus becomes a human being. Supreme Court Justice Harry A. Blackmun, writing for the 7-2 majority ruling in the 1973 Roe v. Wade decision, concluded: “When those trained in the respective disciplines of medicine, philosophy and theology are unable to arrive at any consensus, the judiciary, at this point in the development of man’s knowledge, is not in a position to speculate as to the answer.”

The problem is one of logic, not knowledge. Legal and political decisions are grounded in binary logic in which unambiguous yeses and noes determine final Truths. The law must make a determination on a case, a hard and fast ruling by which we are to abide. And political issues are settled by a consensus process called democracy. By contrast, science is grounded in fuzzy logic in which ambiguous probabilities determine provisional truths. Error bars accompany data graphs, p (probability) values are designated in decimal percentages indicating the likelihood of chance accounting for the finding, and caveats and cautions are sprinkled throughout conclusions.

In the abortion debate here is how the difference between binary and fuzzy logic plays out. Most Pro-Lifers believe that human life begins at conception — before conception not-life, after conception, life. Binary logic. Binary life. With fuzzy logic we can assign a probability to human life — before conception 0, the moment of conception, .1, multi-cellular blastocyst, .2, one-month old embryo, .3, two-month old fetus, .4, and so on until birth, when the fetus becomes a 1.0 human life form. Fuzzy logic. Fuzzy life.

The process does not sound very romantic, but from a scientific perspective human life is a fuzzy continuum. Neither egg nor sperm is a human individual, nor is the zygote or blastocyst because they might split to become twins, or stop developing and naturally abort. The eight-week old fetus has recognizable human features such as face, hands, and feet, but neuronal synaptic connections are still being made so thought is not possible. Only after eight weeks do embryos begin to show primitive response movements, but not until seven months does the fetus develop sufficient neocortical complexity to exhibit some of the cognitive capacities typically found in full-term newborns (in between, the fetus may respond reflexively to stimuli but this in no way can be construed as sentience). Fetus EEG recordings with the characteristics of an adult EEG appear at approximately 30 weeks. In other words, the capacity for human thought does not exist until just six weeks before birth.

Autonomy is also an issue. Between two and six months the fetus could not exist on its own because such critical organs as the lungs and kidneys do not mature before that time. For example, air sac development sufficient for gas exchange does not occur until at least 23 weeks after gestation, and often later. Since virtually no abortions are performed after the second trimester, and before then there is no scientific evidence that the fetus is an autonomous thinking human individual (most scientists agree that of all the characteristics used to define what it means to be human, the capacity to think is the most important), the case for abortion as murder cannot be based on scientific grounds.

Unfortunately, fuzzy thinking often prevails over fuzzy logic, where morality, politics, and science are confoundedly conflated. Moral issues are personal. Political issues are social. Scientific issues are factual. Pro-Choicers believe that whether a woman decides to abort a fetus or not is a personal moral issue. Pro-Lifers want to make it a political issue in which society makes that choice. The fuzzy logic of science reveals that there is no consensus on when a human life begins because it unfolds along a quantitative scale. Therefore, although one may oppose abortion for personal reasons, there is no scientific justification to shift the abortion issue from the personal to the political.

This article was first published here.

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16 Comments to “Fuzzy Logic & Fuzzy Life”

  1. Jocelyn Mandryk Says:

    I think this article raises some very crucial points about the interplay between science, politics, and social vs private issues. First and foremost, that neither can exist in a vacuum, and secondly that the supremacy of science, no matter how probable the evidence, is often NOT the determining factor in political decisions.

    Whether or not science has yet come to a sweeping consensus on when human life actually begins may be a political issue that needs no real answer. The reality is that politics consistently ignores science to meet its own ends or more specifically the interests of those in power. We have witnessed such manipulation time and time again from the advent of atomic energy to the current debate on climate change.

    The matter of abortion is likely not all that different. The infamous trial of Roe vs Wade was informed by science, but politically and legally, it could have gone either way. Science may soon be able to more decisively pinpoint when human life actually begins, but the ability of science to inform is not weighted equally with its ability to influence.

    The logic of science may be fuzzy when it comes to abortion, however the politics is such that we can remove “logic” from the equation altogether.

  2. Christina Says:

    I think this article is yet another example of the perversion of human morals and the thinking pattern that many people follow to make excuses for their own wrongdoing. You wouldn’t be pregnant if you hadn’t had sex in the first place. The reason given to defend abortion is often rape situations, but if you look at the percentages of rape victims that actually end up pregnant you will see that it is very small and therefore should not be considered a legitamate excuse. To any human being with common sense life begins upon impregnation. If it’s not alive, how can you be pregnant? Every living thing grows. If it’s not alive, how can it grow? Name one thing that is not living, but upon completion of growth all of the sudden is deemed living? Have any of you ever seen the video “The Silent Scream”? That child wasn’t at 30 weeks gestation, but it sure as heck gave a pretty good sign that it felt what was being done to it. As any ex-abortionist or abortion assistant. They will tell you stories of babies who have not yet reached this 30 week status of living, and when they’re in a bowl on a countertop or in a plastic trash bag moving and struggling you better believe they know what’s going on. Just because a child has not yet reached the physical capacity to function outside of the womb does not mean that it is not alive. That’s why it’s called an unborn baby. It’s a baby that hasn’t been born. And if that logic isn’t enough for you, think about it like this. Every living creature has a heart. Therefore, every living creature has a heartbeat. A baby’s heart starts beating at 18 days. If that’s not a sign of life, I don’t know what is. Personally, I think it’s pretty sad that more effort is being done to save trees and animals than the millions of little babies that aren’t even acknowledged as human beings.

  3. Tad Says:

    Politics preys on science to tear it down, yet it survives on science’s carcass. You’ve done well to unwrap the fuzziness of the whole debate.

    But these whacky godmen are dousing the debate with weird ideas like when the embryo gets ensouled. Selective passages from scriptures are sassily used.

    I was just wondering to what extent does personal choice trump over everything else. Should this personal freedom remain isolated or intersect with other freedoms (societal or otherwise)?

  4. Laura Rift Says:

    This article hits the nail on the head. It is not a question of unborn life not being alive. OF COURSE, an embryo or a fetus is alive. The question is: At what point to we assign an embryo or fetus the rights we accord a born human being, that is, at what point to we consider the unborn human a PERSON? And what are the moral, political, and social consequences of assigning rights before birth?

    The so-called pro-lifers have not thought this out carefully, but I suspect that on some level they understand that the consequences of enacting laws that extend rights to the unborn would be dire (for instance, mandating the burial of miscarriages and charging women who have abortions with murder). This, I believe, is the real reason that abortion is still legal despite perhaps a majority of Americans believing it to be immoral.

  5. Andrew Luke Says:

    Shermer conflates “fuzzy logic” with “probability.” Fuzzy logic refers to the actual truth value of inherently fuzzy concepts. Probability refers to the chance of a proposition being true or false.

    For example, it is a correct application of fuzzy logic to state that China’s economy is less free than that of the United States, and then give it a number (e.g., .3 free).

    However, it is not an application of fuzzy logic to state that China’s economy has X% chance of of becoming free or that it currently has a 75% chance of having a .3 free economy.

  6. Laura Says:

    In regards to Christina’s above comment:

    “As any ex-abortionist or abortion assistant. They will tell you stories of babies who have not yet reached this 30 week status of living, and when they’re in a bowl on a countertop or in a plastic trash bag moving and struggling you better believe they know what’s going on.”
    I worked in a women’s health clinic for years and have witnessed dozens of abortion procedures. Not even one time have I seen anything like what you’re describing. BABIES do not get removed during abortions; in the vast majority of cases, nothing even remotely human-looking can be seen (apart from the patient and medical personnel, of course). Embryos and early-stage fetuses do not understand anything simply due to the fact that they have nothing resembling a brain, which, I hope you’d concede, is pretty important for learning and comprehending things.

    I’d advise you to get information on fetal gestation from an objective scientific source, rather than from anti-abortion films and literature. Also, your understanding of what “life” is seems rather bizarre. A beating heart does not define “alive” in any way; a heart beating due to a charge from a battery is not alive or deserving of moral consideration. It is merely an organ which has movement independently of any person, as is the case with a fetus at that stage (since there is no human “body” to speak of). A heart does not a person make.

    Further, you fall into the trap of “if she never had sex, she wouldn’t be pregnant, so too bad”. That’s neither moral nor logical for the simple reason that babies (read: born living people) are not punishments for behavior that you don’t approve of. It’s also morally abhorrent to force a person to undergo massive physical stresses against their will because you think it would “teach her a lesson”.

  7. Geezis Says:

    Does any life insurance company in the known world offer a policy on a blastocyst or anything identifiable at the moment of conception? Because they ultimately bear the practical economic and financial consequences faced when making social decisions, the coporations and conglomerates that rule our lives will likely be the final arbiters of when life begins, what it’s beginnings look like, and when it’s expendable as a medical necessity.

  8. Flaky Says:

    Adding to Laura’s commentary of Christina’s post, I find Christina’s (lack of) reasoning appalling.

    – The claim that rape victims, who get pregnant due to rape shouldn’t be allowed abortions, because of the rarity of such incidents is absurd!

    – That all living things have hearts is certainly not in accordance with the general use of the term ‘living thing’. Are humans undergoing heart transplantations not alive during surgery? Are plants not alive?

    – Nowhere did Shermer’s article claim that embryos or fetuses are not alive. Even sperm and ova can be considered to be alive. The question is: Is a fetus, about to be aborted, a human? Potential to become a human, having human genes or being alive are clearly not the same thing as being a living human being deserving protection by the law.

    Christina’s reasoning could just about as well be applied to an argument against treatment of cancer. Cancer is rare, cancers grow and it’s alive. The only thing a cancer lacks is a heart of it’s own, although a cancer can start from the heart and be composed of heart cells.

  9. Alex P Says:

    I always liked to take a different tack in this debate. I always say, “Yes, a fetus is a human and alive.”

    In fact, life only began once, a few billion years ago. It’s a cycle of life, after all! So sperm cells? Ova? Alive too.

  10. Gus Spoon Says:

    Yes indeed you have definitely created fuzzy logic!

    The question at hand is not a scientific one but a moral ethical one.

    With no belief in a creator then you can see how humans muddle up the result.

    The very same thing can happen with our laws and liberty!

  11. ROK Says:

    I find Christina’s comment to be a very good argument. First of all consciousness and ability to think and show intelligence should not be the measure for deciding when the fetus is a human. There are thousands of coma patients and ill people who don’t show any kind of ability to think, don’t react to stimulations or show any kind of intelligence. This does not give us the right to eliminate them. The adult has acted irresponsibly and some one else should pay for that. Unfortunately, there are some women who consider a baby to be her good and act as if they had all the rights to do what ever they like.

    A human being is neither a good nor a possession of anybody except his own. And as we are not willing to kill those who are not able to think or feed themselves we should never ever consider killing unborn babies merely because the mother would like to. Of course there are some situations where an abortion is justifiable as in the case of severe health problems for mother’s and child’s life.

    Today we have created a social situation where disagreement to feminine tyranny is considered as politically incorrect and chauvinistic. As if emancipation was subordination to women and not there elevation out of repression but turning it upside down.

  12. tj Says:

    I have some unorthodox views on the abortion so I’m not offended by “fuzzy logic” but you have failed to address a related issue that can’t be ignored when discussing when life begins. What happens for instance when someone accidentally or purposely causes the developing fetus to die? Currently, I believe someone who harms or kills the pregnant mother can also be charged with murdering the unborn child. So how do you factor this in, using your approach?
    Is this just the case of the fetus being an unborn child if the parents are deprived of their developing offspring vs an embryo if they decide they aren’t ready to bring a new life into the world?

  13. Jeff Says:

    I am anti-abortion and think the argument as to when does a human become human is the only point worthy of debate regarding the abortion issue.

    If it we are not human beings prior to birth then the majorting of the pro-choice arguments that it is purely a private decision is irrelevant.
    If it we become human at the moment of birth (moment? hmm) then again there is not argument.

    So as I understand your argument, since we don’t know exactly when a person is entitled to human rights then it is OK to kill it. The problem with this argument as support unrestricted abortion is that the burden of proof is on the person who advocates the killing, not the other way around. Following your logic, someone could make the claim that a newborn (say 10 ten minutes post birth) isn’t fully human (for reasons X, Y, and Z) and be justified in killing it.

    Your argument reguires a very definitive definition of a human being. What exact qualities make someone a human being? This essay doesn’t provide such a detailed definitition and therefore is meaningless.

  14. Skeptic234 Says:

    What are some good books on abortion?

  15. dziadpokemon Says:

    Jeff, remember we are not trying to decide about anything. Instead, we are thinking about “how can science inform the debate” setting aside emotionally charged (Christina) moral and political aspects of abortion. Here we touch only one (of many) aspect of this multifaceted and extremely difficult issue. In my opinion it’s worth discussing scientific (here), religious, moral, social, philosophical (Alex P) and other contexts separately and see how they can influence our view on abortion. Then the quality of our discussion will be better.

  16. Robin Burgess Says:

    “The question at hand is not a scientific one but a moral ethical one.”

    Yes, it’s a moral question. But the answer to the moral question depends on the answer to “When does on become human?” which is a scientific question.

    “First of all consciousness and ability to think and show intelligence should not be the measure for deciding when the fetus is a human. There are thousands of coma patients and ill people who don’t show any kind of ability to think, don’t react to stimulations or show any kind of intelligence. This does not give us the right to eliminate them.”

    Coma patients who have working brains (unlike fetuses) shouldn’t be killed. People who are brain dead, don’t exist anymore and can’t come back. So, we shouldn’t terminate people who aren’t brain-dead. But keeping the body of someone who is brain-dead alive is just a waste of resources.
    A human may exist as merely a body, but that is not what is important. It’s the existence of a mind (even if one that doesn’t work very well) that really counts. I find it odd that it’s usually the ones who believe in souls that don’t understand this.

    “What happens for instance when someone accidentally or purposely causes the developing fetus to die?”

    I would have thought this obvious. Pro-choice people want to give the choice to -the mother-. Not anyone else.

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