You are right, Brian Greene is a serious physicist as is Carroll and Tegmark – but the books are popular science, for a wide audience. Being interested in this stuff, so to speak, is fine – I read tons of it. Sort of a hobby, as I would have been a physicist were it not for the Civil Rights and anti War movements turning my life away from my talents and toward responsibilities. BUT, letting what is in such books disturb you about the world you can see all around you, is not a good idea. If you and Brian were in a room, and you said to him, hmmm, the future is already written. So why are you angsting over deciding whether to write another book or visit the Great Barrier Reef – he would look at you and wonder what got into you, not it was him who got into you. James’s view is fine. So are others. Because ultimately this is mostly conjecture and, in any event has few if any implications. Suppose you really believe that what you will do next Thursday was decide before you were even born. I think there is no scientist that believes that – but let’s say you did. So it is next Wednesday night, and you are deciding whether to work Thursday, or go to the Great Barrier Reef. Do you think about it any differently? No. I don’t think so. So, I would say, don’t worry about it – there is plenty that really does have implications, not to mention being far more reliably true, to worry about!