Consciousness — the “I” in “I am” — is the self-aware identity that emerges, somehow, in human beings from a weird gestalt biological substrate of 100 billion neurons networked across 500 trillion synapses. It’s a confluence of limbic experience, reciprocal associative memory in symbiosis with multi-processing cerebral cortex. Ironically it eludes precise definition except in metaphysics and yet the four hundred year old metaphor “I think therefore I am” as an epithet for the self-aware homo sapiens remains unimproved to this day.

Consciousness is mysterious in and of itself. It can't be mapped by any current technology. It can't be simulated by any branch of modern science, such is its complexity. The most ambitious synthetic intelligence, on a scale closer to science fiction than anything conceivable today, builds at best a general intelligence - an A.I. - we admit would be closer to zombie than sentient life. But spend a moment reflecting on the sheer complexity of the organ responsible for emergent self awareness. The neurosynaptic network of a single human brain has taken billions of years to build, constructed out of cells, each cell a complex organic computer, 100 trillion atoms, more cells than there are stars in the entire observable universe. Look at a picture of our galaxy, then a Hubble image of the deep field, representing a mere thumbnail sized spot of the night sky. How many thumbnails would it need to cover the entire sky? What inconceivable number of stars would all those galaxies contain? We deduce that consciousness is in there, somewhere, but the how, why and where continue to defy all attempts at direct observation. Small wonder.

Notwithstanding the awe-inspiring mechanics of the brain, we observe our conscious self-aware identity as if it’s a continuous feeling and that this denotes a continuous existence i.e. a thing that is and was and will be, for at least as long as we live. The brain is a wily organ, however, and has had a long time to work out shortcuts and efficiencies. The sense of continuity is important for confidence in our own identity - for it to feel like something we can trust - but in truth that doesn’t mean it has to be continuous; only that it needs to feel that way. Whether or not one believes this to be the truth, recognising the possibility is a more liberating realisation than might first appear.

Consciousness, as a phenomenon, is best described as a persistent rather than continuous creation, blipping into existence moment to moment like the frame-rate on a screen. The blip rate is too fast for us to be aware of our brains fill in the gaps anyway, like it does the blink of your eyes when not focusing on the eyelids. The self becomes an event, manifested in the moment; by the brain, from the brain. It feels continuous. It seems persistent, to itself, because the mind doing the recreating is also in command of any introspection and - objectively - the brain carries the same state (mostly) from one moment to the next. There's enough consistent persistence for us to live out the vicissitudes of existence and the limbic experience of daily life without losing faith in the robustness of our egoic individualism.

This perspective on consciousness gives interesting play to ideas like multiple personalities. Dissociative Personality Disorder is actually no less plausible than a mind with a dominant single personality. Both are moment to moment creations of the brain, concurrent yet separate. It’s capable of manifesting any version of identity at any given instance. There’s no reason to suppose one particular conscious self will be less convincing (to the person experiencing it) than another nor that the foreground identity need be aware of any absence since its last manifestation e.g. when supplanted by a different personality.

So long as your conscious self is given absolutely convincing neurological feedback - if ever interrogated - there's no way to know absolutely what came before the present second or how long in real time your current identity has been in the boss seat. You could just now have flashed into existence in a rebooted universe simulation on some alien supercomputer. How do you know this isn’t the case? The brain can feed you a completely authentic sense of continuity. How could we know we're not just such an alien computer program?

But let’s assume we’re not living in a simulation and instead focus closer to lived experience. Sudden alterations in brain-chemistry can be personality changing - convincing, apparently authentic - without permanently disturbing the substrates of the mind itself e.g. naturally induced or narcotic states. Consider being drunk or on drugs, tripping on hallucinogens, experiencing hypnosis, periods of bipolarity, even intense everyday states like idealised loving or intense loathing. Artificial or unusual short-lived states of mind feel as authentic as long-lasting sober equilibrium. Familiarity is after all no more than a feeling too. The differences tend only to be noticed post-experience.

The brain is conditioned, from birth, to normalise instances of cognitive dissonance into an undisturbed flow of experienced time and even when the conscious self must rationalise periods of lost time, it does so with ease. We lose consciousness daily, when asleep, but accept and integrate this nightly self-annihilation. We cope with the breaks in conscious continuity when taking 'forty winks'. When the brain hasn’t the resources to keep up a steady flow of conscious identity - when we’re very tired, for instance - spasmodic phasing in and out becomes apparent. Still, we cope.

These various gaps in continuous identity are navigated seamlessly so they're irrelevant to lived experience but this is may signpost a profound truth about consciousness. There’s a question often posed by exponents of the ‘self-as-illusion’ hypotheses: “where is the actual you?” an experienced meditator might ask. It’s a provocative notion and it’s impossible to answer without being vague ("I am inside my skull") or speculative ("I am somewhere in my brain") or resorting to symbolic allusions that sound deep but say little ("I am everywhere, I am stardust, I am an immortal essence of life").

What, then, can be said about consciousness? You are emergent. You are a property of the brain; probably. But there is no essential you at a single locus in space, no particular region of the brain containing a definitive clump of synapses and neurons that construct your actual identity. Moreover, the self, as an emergent property, is susceptible to dissolution e.g. through advanced meditation and in this state can be said to not exist at all.

Asking "where is the actual you?" misses the point, however, because in reality the conscious self - that which identifies as you - is not a thing in three-dimensional space. It isn't a where but a when. It's an event that persists, a child process of the neural substrates. It's a phenomenon rooted in time but not fundamental to space; at least not any one point in space over another. This logic is a game changer when it comes to thinking about conscious identity both now, in an everyday psychological sense, and in the future, when the world will have been transformed beyond recognition by technology.

Our Darwinian inheritance is a kind of 'meat vessel' but there's no reason to think it'll always be thus. Liberating consciousness from the fragile and limited primate brain has been a science fiction goal for centuries. Eventually, in some future technological world, even if we assume we’re unable to break the speed of light or meaningfully manipulate time, the where will nonetheless become mutable. We’ll build transports with enough power to pass through interstellar space and attain speeds that might reach the nearest stars in decades rather than millennia. We’ll develop synthetic intelligence to a point we can store brainstuff, consciousness uploaded into the cloud, downloaded into a post-cryogenic body (e.g. your own, if you happen to be sentimental about your particular slab of organic flesh).

Once this happens, existence will have migrated into a universe of when, no longer confined in a prison of where. What are currently astronomical distances in three dimensions become relative (i.e. potentially traversable) once the where and the when separate. It’s easy to conceive of consciousness one day being able to survive such a schism and once it does: watch out universe! Earth will, at last, loose its precious seeds, scattering consciousness by the billlions across an unsuspecting galaxy.

We won’t be bound to flesh and blood once this diaspora begins. We won’t any longer be recognisably homo sapiens. That won’t mean we’ll have ceased to be human, however, and perhaps one of the most profound challenges of the coming centuries will be to somehow navigate the ongoing technological transformation without losing what’s most precious about individual human identity.