If you think Larry was once a tiny embryo, is it inevitable that you will think his life started at the moment of conception? Olson says no, and Baker basically agrees; if Larry existed way back near the beginning of your pregnancy, his history couldn’t go back as far as day one. The two agree that the fetal organism—whether Larry or not Larry—doesn’t start to exist that early.

Ifyou’re willing to think of a very immature embryo as Larry (I’ll go with Olson’s view, to keep things simple), why stop there? In fact, there are some pretty compelling reasons not to think Larry’s life begins at the very beginning of your pregnancy. I first encountered these reasons in a surprising source: a fascinating book called When Did I Begin?, published in 1991 by Norman Ford, a Jesuit priest. By closely examining the biological facts about embryogenesis, Ford casts considerable doubt on the Super Early Larry View—the view that he existed as a one-cell zygote and onward. Ford’s views have been found convincing by Olson and quite a few other philosophers, but don’t seem to have made their way into mainstream thinking about the beginning of life.

One reason for doubting a Super Early entry point for Larry has to do with the first few days of embryogenesis. The one, unified, continuous individual that is Larry can’t have its beginning in the first few days if there is no single, unified individual in the first few days. And arguably there isn’t. The rapidly multiplying cells (two, then four, then eight, etc.) are much like marbles in a bag, the bag being the zona pellucida that was once the wall of the egg. That’s all the unity they have, says Ford: being together in the bag. The cells aren’t part of a multicellular organism yet, because they don’t work together to do the usual things organisms do, such as obtain nutrition from the environment. The cells divide, so there are more of them, but the collection doesn’t grow in volume. Philosophers Barry Smith and Berit Brogaard point out that the collection also has no defense system to maintain stability. If one cell is plucked out, it’s simply gone.

As it turns out, the cells may actually have a little more unity than a bag of marbles. Recent research in embryogenesis (see Pearson in the Bibliography) suggests the dividing cells may not be quite so jumbled. In fact, the collection of cells may even have axes—a top and a bottom, a back and a front. One researcher has suggested that the axes are determined by the exact point where the sperm penetrated the egg. However, this sort of unity may not be enough to make the collection of cells count as a unified organism. At this point the conceptus has the spacial unity of a flock of birds, not the functional unity of an organism that gets nourished, grows, and maintains its stability. And perhaps that’s not really surprising. After all, the cells are very special. Each one of them, just like the original one-cell zygote, can initiate a separate fetus. If this happens when there are two cells, you will have twins; if when there are four cells, you will have quadruplets, and so on.

In fact, when there is actual twinning, instead of only potential twinning, the case against the Super Early Larry View becomes especially compelling—even irrefutable. Suppose Larry has an identical twin named Barry. We can imagine the twinning happening at the two-cell stage, though most twinning happens later. Two processes of embryogenesis ensue, one starting from cell A and one from cell B. A is a distinct entity from B, and Larry at one month will be a distinct entity from Barry at one month. But then, that means Larry doesn’t start life as the zygote, because if he did, Barry would have too, and we’d get a contradiction. Larry is not Barry. But suppose Larry was the zygote and Barry was the zygote too. Then Larry would be Barry. He would be and he wouldn’t be. That being impossible, we have to conclude that when actual twinning takes place, each twin does not start life as a zygote. The zygote is merely a precursor of Larry (and a precursor of Barry), but doesn’t become Larry (or Barry).

Most of us don’t have monozygotic twins, so we shouldn’t make too much of the argument from twinning. But let’s return to singleton Larry. There is a pretty strong case that he doesn’t exist as a two-, four-, eight-, or sixteen-cell conceptus, because that’s a collection of things, not a unified individual; and so he also doesn’t exist any earlier, as a zygote. But what about a little later, on days four, five, or six, for example? To think about this question, we need a few more facts about embryogenesis.

The cluster of cells keeps dividing within the zona pellucida, which is the outer shell left over from the egg, and can’t expand much. Thus, the cells get progressively smaller. Then, on about the fourth day after conception, the outermost cells (about one hundred of them) start to become compacted, so that there’s an outer layer of flattened cells, the trophoblast, and a fluid-filled cavity in the middle. Within the cavity, at one pole, the embryoblast or inner cell mass (a mere twelve cells) forms. With these changes, the conceptus has become a blastocyst. Then, on day five, another major change takes place: the blastocyst hatches out of the zona pellucida. Without that constricting sac, the blastocyst immediately starts growing, and the inner cell mass starts differentiating. Some of it, in combination with the trophoblast, will become the placenta, amniotic sac, and other support structures, but most of it will go into making the fetal body. On about day six, the blastocyst completes its journey through the fallopian tube and implants in the uterine wall.

With that general picture in place, take the blastocyst on day four, with its outer trophoblast shell and its inner embryoblast. If the collection of cells that existed earlier was a mere collection, and not Larry, is the blastocyst enough of a unified system to count as an organism, so that it could be the earliest incarnation of Larry? Certainly it has much more unity than a bag of marbles, but it doesn’t have all the earmarks of an organism. It still doesn’t grow (because of the constricting zona pellucida), and still doesn’t have a way of maintaining its own stability. But there’s another reason to wonder whether the blastocyst is the beginning of Larry. The blastocyst contains the makings of both the later embryo and all of its support structures. In fact, 85 percent of the blastocyst will turn into support structures and just 15 percent will turn into the fetus. If the blastocyst at four days continues on as something, it continues on as the totality of the fetus plus its support structures. It doesn’t continue on as the fetus alone. If Larry your five-year-old traces back to the mature fetus on its own, and the mature fetus on its own doesn’t trace back to the whole blastocyst, then Larry doesn’t trace back to the whole blastocyst.

But couldn’t we say the fetus traces back to a part of the blastocyst—the embryoblast (also known as the inner cell mass)? No, we really couldn’t, for reasons that have to do with the geography of the embryoblast. The embryoblast will develop partly into the fetus, but also partly into the fetal support system. What’s missing from the embryoblast on day four is complete differentiation. There’s partial differentiation, but that’s all. With only partial differentiation, the rudimentary fetus and rudimentary support structures are still somewhat merged together; thus, there is nothing that can be singled out and identified as the earliest incarnation of the mature fetus; and consequently, nothing that can be identified with Larry your child.

Now, this reasoning assumes Larry your five-year-old traces back to the fetus alone, and not the fetus-plus-support-structures. And that’s at least initially quite plausible. It’s natural to think he was once just the resident of an amniotic sac, nourished by a placenta, much like as a five-year-old he’ll be just the resident of your house, and nourished by the refrigerator. But you might think differently about this. To defend a Super Early View, on which Larry starts off as the blastocyst, you might say that Larry traces back to the fetus plus its support structures. He was once an entity with an amniotic sac and placenta as parts, in contrast with how five-year-old Larry will never have your refrigerator as a part. Pressing the idea further, you could say that the organs of mature mammals are "under the skin,” but the organs of immature mammals are not. These external parts of Larry are shed at birth, like later in life he will shed fingernails, hair, and dead skin cells. It’s not common sense that we have an amniotic sac, a placenta, and so on, as parts of ourselves when we are very, very young, but it’s not out of the question.

Around fourteen days after conception, when the primitive streak develops (the first sign of an emerging spinal cord), full differentiation has taken place: a distinct part of the embryo is fetal and other parts are support structures. The later fetus, taken as separate from support structures, can thus be traced back to the fetal part of the fourteen-day-old embryo. If you regard Larry as just a fetus, and believe the support structures are never a part of him, you can trace him back as far as about fourteen days, but no earlier. Before then, the conceptus is a fusion of fetal and support structures, so there is no part of it that can be identified with Larry in his most primitive form.

So it looks like there are two coherent stories here: one where Larry begins to exist as a whole blastocyst at about four days and later has the placenta, amniotic sac, and so on, as temporary parts, to be later shed; and one where Larry begins to exist as part of the implanted embryo at fourteen days, and never at any point has the placenta, and so on, as parts. But there is no coherent story where Larry is the conceptus on days one, two, or three. I conclude that Larry starts to exist as roughly a four- to fourteen-day-old embryo, but certainly not as the zygote on day one. In the style of Charles Dickens, Larry’s life story would begin: not “I am horn’,’ but rather, “I am a slightly developed embryo.”


Our topic is not abortion, since I’m presuming that you, dear reader, are deliberately pregnant and eager to become a parent. But miscarriages happen, and miscarriages can make us feel both devastated and puzzled (though mostly devastated). What have we lost, when we’ve lost an embryo or fetus? Well, we’ve lost the future we hoped for, at least temporarily; that much is clear. But what was the nature of the entity that is gone? This chapter’s theoretical perambulations have a bearing on that question.

If there was no fetal organism before day four or perhaps day fourteen, then some extremely early miscarriages (many happen before we even know we’re pregnant) stop a life from beginning, as opposed to ending a life that has barely begun. A very early miscarriage of a very young embryo is not literally the loss of a child-to- be, because a child-to-be didn’t exist yet and thus couldn’t be lost. An extremely early miscarriage can be mourned to the extent that it dashes hopes (at least temporarily), but it’s not the loss of a life that has already started.

Of course, most miscarriages occur after the first fourteen days of gestation. According to the Early Larry view, these miscarriages do involve the ending of a life that has already begun. Yet in the first weeks of the first trimester, it has barely begun. Larry, at that point, is certainly not yet a baby, child, or adult; in fact, he is not yet a person (on a definition of personhood anything like Baker’s) and not yet a conscious self. But yes, a life has begun—a being already exists who will later be a self, a person, a child, an adult, if the pregnancy continues.

With such a mixed description of an embryo or fetus, you would clearly need to do much more to arrive at a view about miscarriage or the ethics of abortion. All I have tried to do here is address a very basic question we find ourselves thinking about, as we go through pregnancy. What am I seeing in that ultrasound image at eight weeks; who or what is kicking at eighteen weeks? Is it merely a fetal organism, or is it the child I will later hold and cuddle and walk to school? A full defense would take much more space, but the best answer may very well be: the child—but the child prior to entering that special phase of life when he or she will have become a self or a person.

Fast-forward now to nine months after conception. It’s time for baby to be born. Would a philosophical parent prefer natural childbirth, even at the price of greater pain? Or is that downright irrational?

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