In his experience, two qualities were required above all to be a successful prime minister. First, the efficient dispatch of business. And second, optimism. Optimism ! There was simply no point in giving way to despair. It sapped one’s energy, confused one’s thinking, spread like a contagion among one’s colleagues and subordinates, solved nothing, made matters worse. He knew that some people interpreted his equanimity as complacency. It didn’t bother him. He was prime minister, and they were not.

Robert Harris: Precipice