Time travel makes you invincible. Sorta.

I like the idea of being able to travel through time. Who wouldn't like to go back and see some of history's most significant events, like the birth of Jesus (assuming it actually happened), England winning the World Cup in '66 or that day I got kicked by a goat when I was a child. I don't think that I'm ready for the causality of it all though. I mean, it's bound to have an impact, right? The smallest change in the past could damage the future. Or could it?

Surely if I went into the past and tried to change something, I couldn't. I mean, it's already happened, right? And if it's already happened, then I would have always have gone back and created that change. It's like the grandfather conundrum. Could you go back and kill your grandfather before your father was conceived? The answer is no, because if you were to go back and kill him, then your dad - and subsequently you - would cease to have ever existed, and if you never existed then you can't have gone back and killed him. Does that mean that if you went back in time, everyone in your family tree would be invincible to you? I don't know.

Man, I've got to stop watching Lost.

If I do ever go back in time though, I'm taking this. Need to be prepared after all.