‘I wish it were possible’, wrote the American polymath Benjamin Franklin in 1773, ‘to invent a method of embalming … persons, in such a manner that they might be recalled to life at any period.’ Two hundred and fifty years later, Ariel Zeleznikow-Johnston, a young Australian neuroscientist, argues in this riveting book that we not only can but also should cheat death by means of a mind-bogglingly complex process called vitrifixation. This involves posthumously draining the body of fluids and replacing them with an anti-freeze compound called cryoprotectant before storing the body at minus 130 degrees centigrade until such time as it might be reanimated in a world in which medicine has advanced sufficiently to treat deadly human ailments. 

Not only should our bodies be cryogenically frozen. Our brains should also be infused with fixatives such as formaldehyde and glutaraldehyde in order to stabilise neurons, synapses and complex molecules. This would successfully preserve what neuroscientists call the connectome. What, you might be wondering, is a connectome? The word is a neologism, coined in homage to the term ‘genome’. ‘In containing and specifying all of your mental attributes … and in uniquely defining you out of all the other people who could be, your connectome is the physical manifestation of your personal identity,’ Zeleznikow-Johnston explains. Your connectome is substrate neutral, meaning that it can, in principle, be digitised and downloaded from your body. It might even be possible to use the connectome to create a digital avatar with no physical form which will quite happily inhabit virtual reality forever.

The devil, as you might suspect, is in the detail (I found myself writing ‘Really? How?’ in the margins a great deal). When the cryogenically frozen are defrosted back to life, existential problems are likely to arise. Being thawed, then digitised and uploaded to a new body might well be