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Black holes

Laplace's Demon

In a treatise about causal determinism, A Philosophical Essay on Probabilities, Laplace proposes an imaginary all-knowing intelligence ["Une intelligence... Rien ne serait incertain pour elle, et l'avenir comme le passé, serait présent à ses yeux." (An intelligence ... nothing is uncertain to it, and the future like the past is like the present to its eyes)] :

"We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present to its eyes."

Laplace did not use the term 'demon' - it was attributed later, in a similar vein to Maxwell's demon (a thought experiment demonstrating a potential case of violation of the second law of thermodynamics).

Black Holes

Content © Andrew Bone. All rights reserved. Created : January 17, 2016 Last updated :March 26, 2016

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