Agency and purpose: Agency is becoming something of a buzzword in some biological circles, especially those concerned with processes of cognition. The trouble is, no one seems able to agree on what it means. Intuitively, we might suspect that what distinguishes living organisms from nonliving matter is this notion of agency: they can manipulate

Multicellular animals, or metazoa, emerged during the Precambrian period; the earliest fossil evidence for them dates back to around 635 million years ago.

Arguably it is here that we begin to see how life is not a mechanical process that transmits information and organization steadily and predictably along linear pathways from genes to ever increasing scales. Instead it is a cascade of processes, each with a distinct integrity and autonomy, the logic of which has no parallel outside the living world.

As philosopher of science Daniel Nicholson puts it, “The view that genes are the primary causal agents of all the phenomena of organismic life is not well supported by the findings of contemporary biology.” This much, at least, seems uncontroversial. And yet—and yet!—these correlations persist, and genotypic changes and phenotypic changes often

Just as there are physicists who will tell you that everything that happens can ultimately be explained by physics alone (it can’t), and chemists who tell you that in the end biology is just chemistry (it isn’t), so by asserting the primacy of the gene, geneticists are establishing an intellectual pecking order when they attribute more to genes

Weinberg’s vision of a universe without purpose or meaning has become so much the scientific orthodoxy that it is almost obligatory for biologists to insist on it too. Words like purpose, meaning, even function, are treated with a caution bordering on disdain in the life sciences. At best they are corralled with scare quotes that proclaim them mere

One of the fundamental messages of this book is that we cannot properly understand how life works through analogies or metaphorical comparison with any technology that humans have ever invented (so far). Such analogies may provide a foothold for our understanding, but in the end they will fall short, and will constrain and even mislead us if we

Rather, living entities are generators of meaning. They mine their environment (including their own bodies) for things that have meaning for them: moisture, nutrients, warmth. It is not sentimental but simply following the same logic to say that, for we human organisms, another of those meaningful things is love.

Too often, causation in biology, as indeed in the world in general, has been assumed to start “at the bottom” and filter up—so that, for instance, characteristics at the level of an organism’s traits are deemed to be “caused” by genes. As we’ll see, we can gain a better understanding of how life works, and how to intervene in it effectively, when