The Science of Discworld (Science of Discworld, #1)

by Terry Pratchett

human activities do increase the carbon dioxide levels, which is why major international treaties have been signed to reduce carbon dioxide output. (Actually taking that action, rather than just promising to do so, may prove to be a different matter altogether.)

‘global warming’ is under way, it need not show up as an increase in temperature anyway (so the name is a bit silly). What it shows up as is climatic disturbance.

If the theory that oil is the remains of plants from the carboniferous period is true, then our cars are burning up carbon that was once laid down by plants. Even if an alternative theory, growing in popularity, is true, and oil was produced by bacteria, then the problem remains the same. Either way, if you burn a rainforest you add a one-off surplus of carbon dioxide to the atmosphere, but you do not also reduce the Earth’s capacity to generate new oxygen. If you want to reduce atmospheric carbon dioxide permanently, and not just cut short-term emissions, the best bet is to build up a big library at home, locking carbon into paper, or put plenty of asphalt on roads. These don’t sound like ‘green’ activities, but they are. You can cycle on the roads if it makes you feel better.

Triploblasts played a crucial role in evolution, precisely because they did have internal organs, and in particular they could ingest food and excrete it. Their excreta became a major resource for other creatures; to get an interestingly complicated world, it is vitally important that shit happens.

It is known that knowledge is power, and power is energy, and energy is matter, and matter is mass, and therefore large accumulations of knowledge distort time and space.

Or you are in Hawaii, for the only time in your life … and you bump into the Hungarian you worked with at Harvard. Or you’re on honeymoon camping in a remote part of Ireland … and you and your new wife meet your Head of Department and his new wife, walking the other way along an otherwise deserted beach. All of these have happened to Jack.

we expect random events to be evenly distributed, so statistical clumps surprise us. We think that a ‘typical’ lottery draw is something like 5, 14, 27, 36, 39, 45, but that 1, 2, 3,19, 20, 21 is far less likely. Actually, these two sets of numbers have exactly the same probability,

The human brain is an irrepressible pattern-seeking device, and it seizes on certain events that it considers significant, whether or not they really are. In so doing, it ignores all the ‘neighbouring’ events that would help it judge how likely or unlikely the perceived coincidence actually is.

‘What would your ancestors say, my friend, if they saw you rushing into the water just because times are a bit tough on land?’ he said. ‘Er … ‘ “Welcome back”?’ suggested Rincewind, trying to avoid the snapping jaws. “Long time no sea’?’ said the Senior Wrangler, cheerfully. The creature begged, uncertainly. ‘Oh, go on, if you must,’ said the Dean. ‘Fish, fish, fish … you’ll turn into a fish one of these days!’

The sexual link is straightforward, too: dreams about sex are very common anyway.

And there may be some new evidence in favour of watery origins for humanity, though not necessarily the full-blooded Aquatic Ape. A common feature of fossil hominid sites is that they are all near water. This makes sense, because Homo sapiens needs to drink a lot, and sweats and urinates a lot. If we had evolved on savannahs, we would have annoyed the hell out of all the other animals there with our incessant peeing.

Ordinary chimps are promiscuous by the standards of orthodox human morality, though probably no more than many humans are. Pairs of males and females will disappear together for a few days, and then form new partnerships … Humans generally mate for life (a term meaning ‘until we get fed up’)