Precondition Quotes (2 quotes)
Thought experiment is in any case a necessary precondition for physical experiment. Every experimenter and inventor must have the planned arrangement in his head before translating it into fact.
'On Thought Experiments' (1897), in Erwin H. Hiebert (ed.), Erkenntnis und Irrtum (1905), trans. Thomas J. McCormack and Paul Foulkes (1976), 184.
We cannot cheat on DNA. We cannot get round photosynthesis. We cannot say I am not going to give a damn about phytoplankton. All these tiny mechanisms provide the preconditions of our planetary life. To say we do not care is to say in the most literal sense that “we choose death.”
In Maurice F. Strong (ed.), Who Speaks For Earth (1973), 31. In Robert Andrews, The Columbia Book of Quotations (1993), 261.
In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
(1987) -- 
