For someone who studies and admires the ancient Greek and Roman philosophers, as I do, it is disquieting to reflect that these deeply humane ancestors of our own moral thinking were also unquestioning slave-owners. How should we react? Condemn them as wholeheartedly as we do those scientists and other intellectuals who threw in their lot with the Nazis? Or resort to relativism, and maintain that, given the moral code of the time, slave-owning was justified? Neither option is attractive. We must retain our right to condemn slavery wherever and whenever it has occurred, but at the same time recognize that we do not do so from a privileged moral vantage point of our own. History helps us to view ourselves as others will.


What, then, will our descendants justifiably blame us for, as we do the ancient slave-owners? Almost certainly top of their list will be the fact that we continued to trash the environment for them even when well aware of the irreversible consequences of our actions. And by ‘descendants’ I don’t mean some remote future civilization: I’m talking about your grandchildren. There is a near-consensus among climate-scientists that our present levels of greenhouse emissions threaten catastrophic damage, with the danger that large parts of Europe will become uninhabitable. Inevitably some people are self-deluding enough to disbelieve the science. But how about those, including university academics, who are aware of what we are doing, yet are as unwilling to contemplate giving up their comforts as the ancient slave-owners were theirs?

The most damaging thing you can do to the planet in a single legal act is get on a plane. In an international return flight the emission equivalents per passenger typically run into literally tonnes of carbon. And academics fly a lot. Do they have to? To an extent, yes. International conferences, guest lectures and research visits are the adrenaline of academic life. But can any academics truthfully say that they could not halve their flying if it mattered enough to them to do so, by taking the train more often, for example, and by asking themselves which journeys are actually necessary? Many conferences attract participants by their exotic locations as much as by their intellectual value. Almost anybody can find a way of flying less.

Back to the philosop­­hical slave-owners. We would have been unimpressed, no doubt, to learn that they had merely tried to cut down on their number of slaves. But with the harmful practices that pose such an acute threat to our environment the goal is not abolition, it is radical retrenchment. Who will set the needed example of restraint, if our intellectual leaders do not?