AbstractThe plethora of open questions in particle physics, the new chapter opened by the Higgs boson, and the lack of clear theoretical guidance as to where new theory could lie call for a broad and diverse experimental programme boosting the intensity and energy-frontier. The proposed FCC-integrated programme consisting of a luminosity-frontier highest-energy lepton collider followed by an energy-frontier hadron collider promises the most far-reaching particle physics programme that

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... e technology can deliver. In this essay, particular emphasis is given to the lessons from the predecessor of the LHC, LEP, which was commissioned in 1989 and finished operation in November 2000.