"If it is not right, do not do it, if it is not true, do not say it."

Marcus Aurelius Antonius (121 – 180) was Roman emperor from 161 to 180 AD and a Stoic philosopher. He was the last of the rulers known as the Five Good Emperors (a term coined some 13 centuries later by Niccolò Machiavelli), and the last emperor of the Pax Romana, an age of relative peace, calmness and stability for the Roman Empire lasting from 27 BC to 180 AD. He served as Roman consul in 140, 145, and 161. Meditations, the writings of "the philosopher" – as contemporary biographers called Marcus – are a significant source of the modern understanding of ancient Stoic philosophy. These writings have been praised by fellow writers, philosophers, monarchs, and politicians centuries after his death.