The threads that weave the cloth of our mentality are soulless. Our experience of the most beautiful sunset, our most fervent desires, our loftiest thoughts, and our most expansive feelings of love are storms of neural activity, nothing more. Science – and neuroscience in particular – has stripped our mental lives of a soul. But in so doing it has not diminished us in the least.
There are about 86 billion neurons in the human brain – that’s around as many stars as there are in the Milky Way. Those neurons are wired together by more than a tenth of a quadrillion of synapses. Such numbers are nothing short of astonishing in any context. They are made all the more astonishing when we appreciate that they hold true for what goes on in every one of our heads.

What that tenth of a quadrillion of synapses can accomplish is one of the most incredible features of our universe. Before there were brains, the world was just stuff. But once brains evolved, whole vistas of experience were opened whose reality is in no way negated by the discovery of our soullessness. We – our perceptions and dispositions and beliefs – are the orchestrated activity of an entire galaxy of cells, whose branching connections encode our point of view in the world. And that point of view, though it is generated by the tissue confined inside our skulls, contains within it a whole universe of thought and feeling and hopes and fears; it can work at understanding the nature of reality; and, perhaps most astoundingly, it can work at understanding itself. These features of our mental lives are all very real and so very marvelous – even if they are just the product of neural activity.
And I think that such a perspective on our mentality only heightens the profundity of the deepest facets of our conscious lives. I am thinking here specifically of love. When we recognize the soul of a loved one for what it is – activity across trillions of synapses that entwine neurons as numerous as the stars in the Milky Way – we cannot help but feel awed at the miracle of their consciousness. When we love them, we do not love something so simple as a soul. When we love them, we love an entire universe.