What if the moon disappeared when no one was looking at it?;What if time worked differently for each of us?;What if things you could touch were made out of ideas?;What if a decision you made now changed history 10 billion years ago?;What if experiments showed that another dimension exists?;Quantum physics and relativity, two of the most important advances in modern science, are normally presented as a series of technical discoveries in 20th century Europe.Yet this brief, easy-to-read volume shows how they were underpinned by centuries of observations about the nature of reality from the great philosophies and faiths of humanity, from China to India to the Middle East.At each stage, the people involved found themselves saying: "That's impossible! That makes no sense. And yet..."