On the starship Enterprise, an ancient conflict simmers: head versus heart, reason versus emotion, Spock versus McCoy.
Spock is the champion of the rational and the logical: for Spock, emotion is a dangerous foe that needs to be overcome. In opposition stands McCoy, compassionate and fiery.
The dispute between them has a long history. Spock, certainly, would have felt at home among the Stoics – a school of philosophers that flourished in ancient Greece and Rome.
The Stoics held that reason is the only thing that matters; emotion, in contrast, drives people to pursue things – glory, wealth, or power – that do not matter at all. Like Spock, then, the Stoics saw emotion as something to be kept in check.
But emotion has had its philosophical friends too. In the eighteenth century, Joseph Butler argued that emotion is needed because reason is fallible. Even Spock sometimes makes mistakes.
Emotion is needed, Butler thought, to save people from making certain basic errors – neglecting their children or their own safety, say.
An echo of this idea, perhaps, is found in the ‘The Galilieo Seven’ episode, in which Spock, focused on escaping a dangerous planet, is criticised for showing apparently scant concern when a crew member dies.
Butler’s near contemporary, David Hume, took an even stronger view, arguing that without passion, there would be nothing to move us to act at all. Reason, on Hume’s view, steers the ship; but it’s passion that powers the engine.
Like the crew of the Enterprise, Hume might well have wondered whether Spock is really as passionless as he claims to be. Indeed, there seems to be one emotion that Spock is happy to admit to: fascination, after all, looks very much like an emotional response.