It is human instinct to sort, categorize and frame everything in binary black and white. It´s how our brains work. Migrant or refugee? Muslim or Christian? Them or us? Rather than reaching out to those who are different, we bond with those who are just like us, which means the difference between polarized beliefs becomes ever greater. Dangerous possibilities arise. The Arab Spring. Brexit. Trump. Through persistent binary thinking our capacity for rational thought - seeing the grey, rather than merely black and white - begins to erode. Black and White Thinking is an alarm call. Amidst a rising tide of religious intolerance and political extremism, it argues that by understanding the evolutionary programming of our binary brains we can overcome it, make sense of the world and in future make much subtler - and far better - decisions.