Horizon: What is Reality?, BBC Two

Horizon took a funny turn this week. The new series started off gently enough – there was a nostalgic look back at 60 years of science on the box, then an exploration as to what makes us clever (the fun this entailed when vaguely well-known people sweated through a series of IQ tests). But last night it wanted us to get to grips with something very slippery indeed, so slippery that even the eminent scientists responsible for unleashing some of the more frontier theories in particle physics readily admitted their conceptual limitations in understanding their own formulations.

Horizon took a funny turn this week. The new series started off gently enough – there was a nostalgic look back at 60 years of science on the box, then an exploration as to what makes us clever (the fun this entailed when vaguely well-known people sweated through a series of IQ tests). But last night it wanted us to get to grips with something very slippery indeed, so slippery that even the eminent scientists responsible for unleashing some of the more frontier theories in particle physics readily admitted their conceptual limitations in understanding their own formulations.