A Number review – dizzying double-take on the question of cloning

Royal Lyceum, Edinburgh
A crisp combination of stillness and urgency powers Caryl Churchill's teasing speculations on identity

Caryl Churchill's two-hander zips along in an hour, so most evenings there's a talk scheduled beforehand. Presented with the Edinburgh international science festival, each of these conversations picks up on the playwright's theme about the meaning of identity in a hi-tech world. On the night I was there, it was social psychologist Aleks Krotoski and musician-cum-thinker Pat Kane considering the many faces we present to the real and online worlds.

Can we define ourselves as the sum total of our Facebook profiles, Twitter feeds and Instagram selfies? Is any one version of ourselves more true than the others? Or is it that, with or without technology, our sense of self has always been fluid, circumstantial and provisional?