ainst that, youhave possie rmful effects of warming. but i think it is important that warming is happenin in place, that are cold, in place where's it's winter rather than summe and it's summer reasoner nighttim >> rose: what's interesting i that are you not arguing with the facts. you are arguing wit th collusions. >> right >> rose: for examp there's meltg at mont's natul park. is that a gd thing? it's a good thing and a bad thing. >> rose: you don't think that human contribution to global warming as significant as the critics,those who very vehemently oppose global warming and want to doomething about argue. >> that would say we don't know. what wdo know is glaciers wer swinging in stzerland and many other places long before human activity becam ropt. >> rose: let me talk about-- in the context of freeman dyson's remarkable life, here e you in your 80s? what concerns yo today? whato you worry about? >> i wor about nuclear apons. >> rose: have written abt nuclear weons. >> that the number one problem, for me, andll t diussion of global