Eminent geographer Professor David Livingstone wants us to see that climate is more than just the weather outside our window - it's an empire that has shaped our lives throughout history. In the Western world, we live very cushioned lives, so that climate rarely impacts on us in a disastrous fashion. When it does - like the floods that hit parts of the UK in 2007 - we're left shocked and surprised by the ferocity of what climate can do. David explores the way human beings are shaped by weather patterns; "climate has always been a moral issue - not just a description of the weather" he says. In today's programme David explores a very old idea that persists - with no small consequences today - that human culture flourishes in certain climates but degenerates in others. And how that philosophical argument has been used to underpin racist thinking, prevent philanthropical donations, and prevent aid from being sent to Africa.