How to Build a Human: Adventures in How We Are Made and Who We Are. Philip Ball

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СКАЧАТЬ of cultural reference for biomedical advances that unsettle and boggle the mind. But we are sent back to other speculative fictions by some of the possibilities that I have seen seriously and soberly discussed in the context of cell transformation and organoid growth. For example:

       It may well be possible to grow a human brain in the body of a pig. One reason I find this so disturbing is that I still vividly remember first seeing the scene in Lindsay Anderson’s 1973 film, O Lucky Man!, where … well, if you don’t know it already, don’t let me spoil it for you.

       It might be feasible to grow each organ of the human body separately outside the body itself in some sort of vessel (in vitro), and then surgically assemble them into a person – or enough of a person to be, let’s say, a personoid. And this is precisely how the first robots were made, in Karel Čapek’s 1921 play, R.U.R.

       Philosophers, ethicists and neuroscientists are now compelled to debate what it could mean to create a full-grown human brain in a vat. Could it be conscious? Would it experience a self-contained interior “reality”? The pop-culture reference point here, which philosophers have embraced with nerdy delight, is of course the Matrix movies of the Wachowskis.

      Let me make it clear that no researcher sees any prospect of these things happening in the near future, nor any good reason to try to make them happen. I will look at them more closely later, but my point here is not to tell rather shocking and thrillingly grotesque scare stories in a bout of bait-and-switch. What matters is that, confronted with so disorienting and disturbing a set of imaginable possibilities, we seem to need such stories in order to frame our thoughts. That in itself is worth considering. What motivates and shapes these narratives?

      Underpinning them, I believe, is a consideration that might at first strike you as odd: We are not at ease with our own flesh.

      But surely, you might say, we inhabit our own flesh? I’m putting those words into your mouth because they have a familiar ring to them – it doesn’t seem a strange thing to suggest. Yet such a phrase serves more to disassociate than to unite us with our flesh. We inhabit it? Like a person who inhabits a house? So what, then, are “we”? It’s the old Cartesian dualism: the separation of mind and body, or as some might have once said, of body and soul.

      Yet of course we are not at ease in our own flesh! How we recoil from its routine functions, its excrescences and smells and fluids. How hard we try to remodel it, with what horror we watch its decrepitude. How we flock to watch movies like Hellraiser and Saw, or, at the more sophisticated end of the body-horror market, pretty much any of David Cronenberg’s early oeuvre. Gunther von Hagens, with his plasticized corpses, has made a career from an artful exploration of our horrified fascination; artists from Mark Quinn (who has sculpted with his own blood and the placenta of his baby son) to Marina Abramović have made what are often brave, painful and stomach-churning attempts to help us engage with our raw material.

      There are many reasons for this ambivalence towards the somatic aspects of human existence, expressed repeatedly in all cultures in all ages: with piercings and tattoos, rituals of embalming and burial, elaborate taboos and the normative strictures of surgery. But the new sciences of culturing and transforming our cellular fabric confront us with perhaps the most fundamental challenge for our relationship with our flesh. They show us the ultimate in dismemberment: a reduction of the person to the cell.

      Time was when we could dismiss that. Sure, cells are our building blocks, but no more or less so than proteins, atoms or quarks. If a chunk of our cellular material were removed, well, so what? It was no longer “us”, but a piece of waste, separate and dead, soon to be putrescent and doomed by microbes and entropy.

      Having your skin grown into neurons that assemble themselves into a brain organoid is a pretty convincing way to find out how obsolete that notion is. All the more so when you see it through the microscope and realize that this is not merely some trick of preservation. Life on that scale is multitudinous, and thriving, and it has a plan of sorts.

      Life? Whose life?

      Not mine, exactly – and yet who else’s can it be? Those cells are autonomous – but why any more so than the cells still in my arm, in my real brain (the need for that specifying adjective still makes me blink), my surging blood and beating heart? And so I come by degrees to accept the inevitable truth: I am a colony of cells, whose cooperation lets me draw breath, whose communication produces my sense of identity and uniqueness.

      That is what is fundamentally disconcerting about our own flesh. It grew as a colony from a single cell, and we’re not quite sure where (or when) in this teeming morass to pin the label “me”.

      The new cell technologies are making it impossible for us any longer to ignore this fact. I won’t pretend that I know how to normalize it, but I think there is a strange kind of liberation that can come from letting ourselves be unsettled by it.

       CHAPTER 1

       PIECES OF LIFE

       CELLS PAST AND PRESENT

      “Ex ovo omnia.”

      So declared the frontispiece of Exercitationes de generatione animalium (1651) by the seventeenth-century English physician William Harvey, sometime physician to James I. It expressed a conviction (and no more) that all things living come from an egg.

       William Harvey’s motto “All things from an egg” in the frontispiece of his 1651 treatise on the “generation of animals”.

      It’s not really true: plenty of living organisms, such as bacteria and fungi, do not begin this way. But we do. (At least, we have done so far. I no longer take it for granted that this will always be the case.)

      “Egg” is an odd term for our generative particle, and indeed Harvey was a little vague about what he meant by it. Strictly speaking, an egg is just the vessel that contains the fertilized cell, the zygote in which the male genes from sperm are combined with the female genes from the “egg cell” or ovum. Yet it’s easy to overlook how bold a proposal Harvey was making, in a time when no one (himself included) had ever seen a human ovum and the notion that people might begin in a process akin to that of birds and amphibians could have sounded bizarre.

      The truth of Harvey’s insight could only be discerned once biology acquired the idea of the cell, the fundamental “atom of biology”. That insight is often attributed to Harvey’s compatriot and near-contemporary Robert Hooke, who made the most productive use of the newly invented microscope in the 1660s and ’70s. Hooke discerned that a thin slice of cork was composed of tiny compartments that he called “cells”. This is often said to be an allusion to the cloistered chambers (Latin cella: small room) of monks, but Hooke drew a parallel instead with the chambers of the bee’s honeycomb, which in turn probably derive from the monastic analogy.

       Robert Hooke’s sketch of cells in cork, as seen in the microscope.

      The popular notion that Hooke established the cellular basis of all СКАЧАТЬ