The Science of Fate

Why Your Future is more Predictable Than You Think

The existence of the self, self-consciousness and free will are topics of long-standing interest in philosophy and nowadays also in neuroscience. This book deals with free will or, to be more precise, defends its non-existence.

Virtually no neuroscientist or, more generally, no biologist disputes that the traits we inherit are expressed in different ways by virtue of interactions with the environment. We inherit propensities, not perfectly finished traits. And for that reason we should not say that genetic inheritance determines, but, at most, that it conditions.

Obviously, our configuration depends to a large extent on the information contained in the genetic code. This is where traits such as our four limbs, the shape of our head, our bipedal condition, etc. are based. We walk on two limbs and not on four because we have inherited a body configuration that forces us to do so. No one in their right mind would say that we walk on two limbs because that is how we have seen others do it, because we have been taught to move that way or because it is the appropriate way given the shape and dimensions of our homes and furniture.

But things get more complicated as we move from these "big features" to (seemingly) smaller and smaller details. Some of us are shorter, have a higher body mass index and go bald earlier than others. Is that 100% dependent on the genome? Not at all. Does it depend 100% on the environment, on the conditions in which we have been brought up? Not at all. Some of these traits are the result of the interaction between heredity and environment that I mentioned earlier.

When the environmental conditions under which the individuals in a group live are exactly the same, any differences between them must be due to hereditary factors. At the other extreme, if we have a set of identical twins, any differences between them must be the consequence of their having been exposed to different environmental conditions at some stage of their development. Thus, the notion of heritability is relative, and depends on the extent to which individuals have been exposed to different environmental conditions. This notion has far-reaching consequences and I will return to it at the end of this commentary.

Critchlow argues that many neurobiological characters are genetically preconfigured and that the effect of environmental conditions is limited. In contrast to the trend that was prevalent at the end of the last century to attribute most of the neurobiological differences observed between individuals to neuroplasticity and the effect of the environment, she argues that this flexibility ­–this neuroplasticity– is limited and that we are highly conditioned –though perhaps not predestined– to be one way and not another.

The author places herself on the side of those who propose that heredity is more important than is usually attributed to it. Throughout her book, she explains in which aspects of our neurobiology and its correlate –behaviour– this reality manifests itself.

In the introduction, for example, she states: «It is impossible to say that any single action, decision or outcome was fated for us by our genes or hard-wired into our brain, but it is possible to say that someone is predisposed to take certain decisions due to the way their brain was constructed prior to their birth and the genetic inheritance informing its operation over the person’s lifetime».

After the introduction, the author explains in chapter 2 how the brain develops, what happens to it at different points in its development. In chapter 3, she deals with the way in which the brain drives us to eat more than we need and to eat food that is not the most suitable for us. Then, in chapter 4, she deals with affections, bonds with other people, attachments. In chapter 5, she explains the neurobiological basis of perception and how it shapes the way we see and understand reality. In relation to the above, in chapter 6 she goes on to deal with the neurobiological basis of beliefs and what we understand by knowledge. In chapter 7 she assesses the possibilities of predicting neurological and mental health long in advance, so that good therapeutic decisions can be made at the right time. The last chapter, just before the epilogue, is devoted to the cooperative brain and compassion. It also challenges the existence of a ‘human nature’. The author places great emphasis on the fact that each one of us is unique and that it is not possible to refer to all the people who make up the human species as if we were all endowed with the same characteristics.

Going back to the beginning of this review, the author argues that we do not make decisions consciously and freely because we are, to a large extent, conditioned by the neural architecture and the functional organisation of the brain and the nervous system in general. And because that architecture and organisation have been inherited. Moreover, the more homogeneous the conditions under which we grow up –that is, the less differences there are in the characteristics of the environment in which we develop– the more important genetic inheritance becomes in relative terms.

Nothing is perfect, and neither is this book. But I found it to be a good book, due to its content and its easily understandable, entertaining and didactic style.

The book:

Title: The Science of Fate: Why Your Future is more Predictable Than You Think

Author: Hannah Critchlow

Hodder & Stoughton Ltd., 2019.