From Tim Stevenson
Joseph Silk’s article on cosmic conundrums (8 March, p 26) has me pondering on the concepts of causality and explanation. Classical causality relates a known precondition, an established regularity of nature, to the outcome: the apple became unsupported, there is a Newtonian force between masses causing acceleration, the apple fell.
Causality 2, if you will, as used in modern cosmology, simply says that we have cooked up a potage of maths that is consistent with observed reality. This would revert to classical causality were we able to observe a multiplicity of universes and identify a regularity among them. Regrettably, we do not currently have this luxury.
Great Missenden, Buckinghamshire, UK
