I have to say that some philosophers such as the late Bernard Williams, and I would include myself in this group, would say that tranquillity is overrated as the goal of life.

Epicurus was not at all interested in what we would call the problems of mass society, and he thought civic politics was just trouble and to be avoided by the wise.

Morality has in the past made progress when we broadened the category of things we weren't permitted to harm (animals, 'infidels'); saw through some delusions and rationalisations about what harms are good for people themselves (prison punishment, hysterectomies for unhappy 1950s wives); and readjusted our for-the-good of others criteria so as to demand only reasonable sacrifices (ceasing to use children as handy chimney sweeps).

Outside of mathematics and logic, there are common sense truths, such as that it is snowing that normal observers, in a specified context can agree on, subject to vagueness considerations, and theoretical truths, such as that snow is crystallised water vapour, and maybe in-between truths.

Epicurus was in favour of friendly sex but not of grand passions or marriage and children, viewing them as sources of trouble and vexation.

For seventeenth-century astronomers, the Epicurean doctrine of multiple worlds separated by void space was seen to fit with the new Copernican system in which every star was a sun, and the universe was a vast place with no centre.

We have to gamble, and sometimes lose as George Ainslie argues; this keeps the appetite for life sharp.