Moral theory develops from the divine command theory of medieval Christian philosophy, mixed up with a bit of ancient pagan virtue theory, to the purely secular moral sentiment and interpersonal reaction theories of Smith and Hume, to Kant's attempt to restore command theory but with something supersensible in the individual rather than God as the source of authority.

Some critics thought the ontology and theory of qualities absurd. No one had ever seen these little atoms, and furthermore, how could their mere arrangement produce a noisy, colourful, world in which day followed night and animals generated their own kind? Instead of a world created, cared, for and supervised by supernatural persons, the Epicureans appeared to the theologians to be assigning everything to chance. The latter were appalled by Lucretius's view of religion as cruel and oppressive and by the Epicurean insistence that death is the end of all experience.

The (atomic) soul is mortal, and the best life is the one with the least pain and the most pleasure.

In the old systems, hierarchies emanate power from above to below through forms of line management and are ideologically supported by cosmologies and theologies featuring celestial rulers and their deputies - the 'rule of the best.'

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.

About 70% of what I've written about is centered on the clashes and conformities between the emerging life and physical sciences and older metaphysical frameworks in the 17th and 18th centuries. The other 30% consists of one-off essays or researches into other intriguing contemporary topics such as visual experience, aesthetics, social justice issues, and the epistemology of moral knowledge.

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).