Against Time Travel

"Freeman Dyson said a very good argument against the possibility of time travel is that we've never met any time travellers. If someone in the future had done it, someone would have come back." (Pref. Jeff Forshaw, as reported in the Indy)

No, it's a very poor argument. 

Firstly a time traveller would almost certainly be obeying some sort of prime directive- and trying to pass among us undetected.

Secondly, if they broke the directive and announced their identity (but why should they?) we'd simply disbelieve them.

Thirdly if they showed up with signs and wonders (in a UFO for example) the evidence would be placed in the file marked "paranormal" and ruled out of court. 

Urban Warfare

There are kids out the back throwing stones at other kids- some of which land in our back yard- so Aliz and I go out and sort of stand there and quietly object (no shouting) and that defuses things. A small boy (reaching to my elbow, maybe a little higher) aims a final verbal insult at his foes- who happen to be girls, "I have only one thing to say to you:- YOU FAGGOTS!"