BLIND HOPE

Michio Kaku (“Leaving planet Earth”, February 9) calls himself an optimist, but in fact he’s a fantasist. Nothing shows this more clearly than his dismissal of climate change (“2040, 2050, before we see the very visible effects”). A few pages earlier in the same issue, Bernard Lagan ( Bulletin from Abroad) recounts very visible effects in the form of “Australia’s grim record-breaking heatwaves” .

There’s irony in the title of “Leaving planet Earth”: as a proponent of multiple universes, Kaku seems to have left this one for a fantastic alternative universe in which climate change “does not greatly trouble him”. John Miller Crawford (Grey Lynn, Auckland)