“Once you decide on the best poison for the termination, you must work out the correct concentration. For instance, I know that five milligrams of cetratranic acid dropped into a bell-jar with a single moth will take about three seconds to stun it. I know that seven milligrams will anaesthetize it and ten is enough to kill it, providing the moth does not weight more than 3.5 grams. I also know that to kill fifty moths you need five times the concentration or volume of killing fluid, but to kill seven thousand you'd need only two hundred times the concentration. I know that potassium chloride could never kill a larger moth and potassium sulphide would only ever be strong enough to anaesthetize it. I know that cyanide kills anything. But what I don't know right now is the precise amount I will need to kill Vivien.”

“A moth is such a simple machine in the animal world - the go-kart to the modern car - and it takes a lot of glitches to prevent it going. It's this intriguing simplicity, the idea that you could pull it into its constituent parts and put it back together in the same rainy day, that if you pulled back the skin, you could watch the inner workings, that makes a moth such an absorbing creature to study. Moths have a universal character: there are no individuals. Each reacts to a precise condition or stimulus in a predictable and replicable way. They are pre-programmed robots, unable to learn from experience. For instance, we know they will allways react to a smell, a pheromone or a particular spectrum of light in the same way. I can mimic the scent of a flower so that a moth will direct itself towards that scent ...”

“Why would I kill to know what she's thinking right now? Probably because I enjoy killing.”

“I know you are here to kill me. Shoot, coward, you are only going to kill a man.”

“I realise now... the less you know, the more likely you are to kill yourself by accident. And the more you know, the more likely you are to kill yourself on purpose.”

“So ‘fatal’ only kills you two out of three times these days? That’s good to know.”

“Clive convinced himself that it wouldn’t be long before we’d be able to predict all their [the moths] equations of cause and effect, then perhaps even map out each and every cell, and configure them in their entirety as robots, in terms of molecules, chemicals and electrical signals. And what fed this particular obsession was Pupal Soup. If you cut through a cocoon in mid-winter, a thick creamy liquid will spill out and nothing more. What goes into that cocoon in autumn is a caterpillar and what comes out in spring is entirely different—a moth, complete with papery wings, hair like legs and antennae. Yet this same creature spends winter as a gray-green liquid, a primordial soup. The miraculous meltdown of an animal into a case of fluid chemicals and its exquisite re-generation into a different animal, like a stupendous jigsaw, was a feat that, far from putting off, fed Clive’s obsession. He believed it made his lifetime ambition easier because, however complex it might be, it was, after all, only a jigsaw, and to Clive, that meant it was possible. For all the chemicals required to make a moth were right there in front of his eyes, in the pupal soup.”