He says another complication is setting a timescale in stone.
The timescale in which that change will happen and its impact on the UK all remain unclear," he said.
Riley-Smith's arguments had already been sketched out over a much longer timescale in his trenchant What Were the Crusades?
For instance, reversible evolution has been observed on a relatively short evolutionary timescale in the peppered moth (Biston betularia).
What is in contention is the scale of savings and the timescale in which they can be achieved.
All of that is, of course, debatable (right down to timescale: in fact, some of the book is more than 25 years old).
Well, he doesn't really set out a timescale in his 1798 An Essay on the Principle of Population, so the answer has to be no.
Lightman said heads would be able to turn around their schools if they were given a realistic timescale in which to do so, but that there was too much "pressure for immediate results".
Without fully knowing why the damage to the motor neurons, which stretch out from the spinal cord to the muscles, occurs over a much shorter timescale in some patients than others, trying to find drug targets has proved fruitless.
Replacing fossil fuels with renewables, on the timescale in which we need to act, is hard enough, without setting yourself the additional, unnecessary challenge of also replacing nuclear power.
In an interview with the Sunday Herald, the SNP leader says: "Our manifesto will set out what we consider around the circumstances in which, and the possible timescale in which a second referendum might be appropriate.
