The notion of state is a central notion for all branches of physics. Surprisingly enough, Newton's notion di¤ers from the nowadays notion. Our review of the bene...ts of Newton's notion comprises Gibbs's paradox, Einstein's derivation of the classical and quantum distribution laws from the energetic spectrum (serving to remove anthropomorphic elements), the di¤erence between 'identical' and 'indistinguishable' (being a property of states rather than of particles), a new physical content of j

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... t)j (the invariance of j (x; t)j rather than (x; t) against permutations yields not only fermions and bosons, but also anyons), and a novel classi...cation of forces (leading eventually to a derivation of the Maxwell-Lorentz equations from classical mechanics).