If the mass of a hadron is large enough, decays into final states that can be reached by strong interaction, that is, without violating any selection rule, are possible. The lifetime is then extremely short, of the order of a yoctosecond (10−24 s). These hadrons decay practically where they were born. We show how they are observed as ‘resonances’.

Hadrons, both baryons and mesons, were discovered in rapidly increasing numbers in the 1950s and early 1960s. How their quantum numbers, spin, parity and isospin were measured. Gradually it became clear that hadrons with the same spin and parity could be grouped in multiplets of the SU(3) symmetry. Proposal of the quark model and experimental verifications of its predictions. With increasing accelerator energies, more surprises were to come. The quarks are not only the three originally known, u, d and s, but three more exist, c, b and t. And more leptons were found, in total three ‘families’ of fundamental fermions, each with two quarks, a charged lepton and its neutrino.

Not all prime ministers are equal. Not remotely – which is why books taking one prime minister after the other can only ever tell a partial story. In this chapter, we consider the other seven (after Walpole and Pitt the Younger) who defined the office as ‘agenda changers’. They are the creators of the (still evolving) office of prime minister. All nine – two in the eighteenth century, three in the nineteenth, and four in the twentieth – carved out what the office of prime minister means, and shaped the office in their own image. After these ‘agenda changers’ ceased to be prime minister, their successors over the years that followed either tried to be like them, or tried deliberately to distance themselves from them: but none could escape their long shadow. They took advantage of wide-ranging historical or consensus change and moulded the office and country to their will.

Stoicism before Chrysippus believed in radical determism, but Chrysippus reintroduced the notion of human responsibility. He argued that it is in our power to assent to an impression or otherwise and work with it, and it is likewise in our power to assent to or to reject World Fate, working with or against it. He illustrated this with his analogy with the top that needs a spin: its spinnability is its inherent cause, but needs an external cause to activate it. In this way, he further posited, we can assign good or bad morality to humans, judging by their will to live Stoically, that is, ‘in accordance with nature’, the Stoics’ highest virtue. Virgil adopts this model in the Aeneid, so that Aeneas can be seen as learning to assent to World Fate, while Juno, Dido and Turnus can ignore or reject it. Virgil in fact incorporates Chrysippus’ analogy in a simile depicting Amata driven by her inherent desire and by the daemonic goddess Allecto to deny her assent to World Fate. However, he locates deviations from World Fate within the Stoic category of ‘events in suspension’, ‘indifferents’ or individual fortunes, which might temporarily challenge World Fate but never negate it.