We are bad at making decisions. According to science, our decisions are based on oversimplification, laziness and prejudice. And that's assuming that we haven't already been hijacked by our surroundings or led astray by our subconscious!

Featuring exclusive footage of experiments that show how our choices can be confounded by temperature, warped by post-rationalisation and even manipulated by the future, Horizon presents a guide to better decision making, and introduces you to Mathematician Garth Sundem, who is convinced that conclusions can best be reached using simple maths and a pencil!

From BBC Horizon.

Part 1 of 2. First aired Feb 12, 2008.