Much of the misery in the world today — as it always has been — is due to the human propensity to contemplate, or actually commit, violence against another human being. It's not just assaults and murders that display that propensity. Someone who designs a weapon, punishes a child, declares war or leaves a hit-and-run victim by the side of the road has defined 'harming another human being' as a justifiable action for himself. How different the world would be if, as a biologically determined characteristic of future human beings, there was such a cognitive inhibition to such actions that people would be incapable of carrying them out, just as most of us are incapable of moving our ears.
It must be the case that that in the brains of everyone, from abusive parents and rapists to arms dealers and heads of state, there can arise a concatenation of nerve impulses which allow someone to see as 'normal' — or at least acceptable — the mutilation, maiming or death of another for one's own pleasure, greed or benefit. Suppose the pattern of that series of impulses was analysable exactly, with future developments of fMRI, PET scans or technology as yet uninvented. Perhaps every decision to kill or harm another person can be traced to a series of nerve impulses that arise in brain centre A, travel in a microsecond to areas B, C, and D, inhibit areas E and F, and lead to a previously unacceptable decision becoming acceptable. Perhaps we would discover a common factor between the brain patterns of someone who is about to murder a child, and a head of state signing a bill to initiate a nuclear weapons programme, or an engineer designing a new type of cluster bomb. All of them accept at some intellectual level that it is perfectly all right for their actions to cause harm or death to another human. The brains of all of them, perhaps, experience pattern D, the 'death pattern'.
If such a specific pattern of brain activity were detectable, could methods then be devised that prevented or disrupted it whenever it was about to arise? At its most plausible — and least socially acceptable — everyone could wear microcircuit-based devices that detected the pattern and suppressed or disrupted it, such that anyone in whom the impulse arose would instantaneously lose any will to carry it out. Less plausible, but still imaginable, would be some sophisticated chemical suppressant of 'pattern D', genetically engineered to act at specific synapses or on specific neurotransmitters, and delivered in some way that reached every single member of the world's population. The 'pattern D suppressant' could be used as a water additive, like chlorine, acceptable now to prevent deaths from dirty water; or as inhalants sprayed from the air; or in genetically modified foodstuffs; even, perhaps, alteration of the germ cell line in one generation that would forever remove pattern D from future generations.
Rapes would be defused before they happened; soldiers — if there were still armies — would be inhibited from firing as their trigger fingers tightened, except of course there would be no one to fire at since enemy soldiers, insurgents, or terrorists would themselves be unable to carry their violent acts to completion.
Would the total elimination of murderous impulses from the human race have a down side? Well, of course, one single person who escaped the elimination process could then rule the world. He — probably a man — could oppress and kill with impunity since no one else would have the will to kill him. Measures would have to be devised to deal with such a situation. Such a person would be so harmful to the human race that, perhaps, plans would have to be laid to control him if he should arise. Tricky, this one, since he couldn't be killed, as there would no one able to kill him or even to design a machine that would kill him, as that also would involve an ability to contemplate the death of another human being.
But setting that possibility aside, what would be the disadvantages of a world in which, chemically or electronically, the ability to kill or harm another human being would be removed from all people? Surely, only good could come from it. Crimes motivated by greed would still be possible, but robberies would be achieved with trickery rather than at the point of a pistol; gang members might attack each other with insults and taunts rather than razors or coshes; governments might play chess to decide on tricky border issues; and deaths from road accidents would go down because even the slightest thought about one's own behaviour causing the death of another would be so reminiscent of 'pattern D' that we would all drive much more carefully to avoid it. Deaths from natural disasters would continue, but charitable giving and international aid in such situations would soar as people realised that not helping to prevent them in future would be almost as bad as the old and now eliminated habit of killing people.
A method to eliminate 'pattern D' will lead to the most significant change ever in the way humans — and therefore societies — behave. And somewhere, in the fields of neurobiology or genetic modification today the germ of that change may already be present.