Any plea ... for institutionalized risk-assessment, beefed-up bioethics panels, academic review bodies, worse-case scenario planning, more intensive computer simulations, systematic long-term planning and the institutionalized study of existential risks is admirable. But so is urgent action to combat the global pandemic of suffering. "The easiest pain to bear is someone else's".

Taking the abolitionist project to the rest of the galaxy and beyond sounds crazy today; but it's the application of technology to a very homely moral precept writ large, not the outgrowth of a revolutionary new ethical theory. So long as sentient beings suffer extraordinary unpleasantness - whether on Earth or perhaps elsewhere - there is a presumptive case to eradicate such suffering wherever it is found.

One should be wary of assuming that we're the folk who can properly look after ourselves, whereas our descendants, if they become genetically pre-programmed ecstatics, will get trapped in robot-serviced states of infantile dependence. For it shouldn't be forgotten that exuberantly happy people also have a fierce will to survive. They love life dearly. They take on daunting challenges against seemingly impossible odds. One of the hallmarks of many endogenous depressive states, on the other hand, is so-called behavioural despair. If one learns that apparently no amount of effort can rescue one from an aversive stimulus, then one tends to sink into a lethargic stupor. This syndrome of "learned helplessness" may persist even when the opportunity to escape from the nasty stimulus subsequently arises.

It's easy to convince oneself that things can't really be that terrible, that the horror I allude to is being overblown, that what is going on elsewhere in space-time is somehow less real than the here-and-now, or that the good in the world somehow offsets the bad. Yet however vividly one thinks one can imagine what agony, torture or suicidal despair must be like, the reality is inconceivably worse. The force of "inconceivably" is itself largely inconceivable here. Blurry images of Orwell's "Room 101" can barely even hint at what I'm talking about. Even if one's ancestral namesakes [aka "younger self"] underwent great pain, then the state-dependence of memories means that much of pain's sheer dreadfulness is semantically, cognitively and emotionally inaccessible in the here-and-now. So this manifesto's rhapsodies on the incredible joys that do indeed lie ahead tend to belie its underlying seriousness of purpose. For the biological strategy is propounded here in deadly moral earnest.

Negative-utilitarianism is only one particular denomination of a broad church to which the reader may well in any case not subscribe. Fortunately, the program can be defended on grounds that utilitarians of all stripes can agree on. So a defence will be mounted against critics of the theory and application of a utilitarian ethic in general. For in practice the most potent and effective means of curing unpleasantness is to ensure that a defining aspect of future states of mind is their permeation with the molecular chemistry of ecstasy: both genetically precoded and pharmacologically fine-tuned. Orthodox utilitarians will doubtless find the cornucopian abundance of bliss this strategy delivers is itself an extra source of moral value. Future generations of native ecstatics are unlikely to disagree.

No amount of happiness enjoyed by some organisms can notionally justify the indescribable horrors of Auschwitz. Nor can the fun and games outweigh the sporadic frightfulness of pain and despair that occurs every second of every day. For there's nothing inherently wrong with non-sentience or non-existence; whereas there is something frightfully and self-intimatingly wrong with suffering.

The functional regions of the brain which subserve physical agony, the "pain centres", and the mainly limbic substrates of emotion, appear in phylogenetic terms to be remarkably constant in the vertebrate line. The neural pathways involving serotonin, the periaquaductal grey matter, bradykinin, dynorphin, ATP receptors, the major opioid families, substance P etc all existed long before hominids walked the earth. Not merely is the biochemistry of suffering disturbingly similar where not effectively type-identical across a wide spectrum of vertebrate (and even some invertebrate) species. It is at least possible that members of any species whose members have more pain cells exhibiting greater synaptic density than humans sometimes suffer more atrociously than we do, whatever their notional "intelligence".

Much more seriously, in those traditional eco-systems that we chose to retain, millions of non-human animals will continue periodically to starve, die horribly of thirst and disease, or even get eaten alive. This is commonly viewed as "natural" and hence basically OK. It would indeed be comforting to think that in some sense this ongoing animal holocaust doesn't matter too much. We often find it convenient to act as though the capacity to suffer were somehow inseparably bound up with linguistic ability or ratiocinative prowess. Yet there is absolutely no evidence that this is the case, and a great deal that it isn't.

It is easy to romanticise, say, tigers or lions and cats. We admire their magnificent beauty, strength and agility. But we would regard their notional human counterparts as wanton psychopaths of the worst kind.

The Hedonistic Imperative outlines how genetic engineering and nanotechnology will abolish suffering in all sentient life.This project is ambitious but technically feasible. It is also instrumentally rational and ethically mandatory. The metabolic pathways of pain and malaise evolved only because they once served the fitness of our genes. They will be replaced by a different sort of neural architecture. States of sublime well-being are destined to become the genetically pre-programmed norm of mental health. The world's last aversive experience will be a precisely dateable event.Two hundred years ago, powerful synthetic pain-killers and surgical anesthetics were unknown. The notion that physical pain could be banished from most people's lives would have seemed absurd. Today most of us in the technically advanced nations take its routine absence for granted. The prospect that what we describe as psychological pain, too, could ever be banished is equally counter-intuitive. The feasibility of its abolition turns its deliberate retention into an issue of social policy and ethical choice.