There are two kinds of wonder. You may well experience the first when you look at the night sky on a clear and moonless night. The universe is vast, beautiful, and at times incomprehensible. The other kind of wonder can be experienced when someone studies something scientifically: a complex and highly ordered process analysed and understood. I mentioned last week that Ernst Mach didn’t believe in wonder. It was the first kind of wonder that he didn’t believe in: the kind that comes from ignorance and is dispelled by knowledge – a process that can lead to disillusionment. But as Einstein pointed out, when one explores phenomena scientifically the wonder only deepens as the order and complexity in a system reveals itself.