Marcus Aurelius 26 April 121 – 17 March 180 was a Roman emperor from 161 to 180 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.

Meditations, the writings of "the philosopher"–as contemporary biographers called Marcus, are a significant source of the modern understanding of ancient Stoic philosophy. They have been praised by fellow writers, philosophers, monarchs, and politicians centuries after his death.

Marcus acquired the reputation of a philosopher king within his lifetime, and the title would remain after his death; both Dio and the biographer call him 'the philosopher'. Christians such as Justin Martyr, Athenagoras, and Melito also gave him the title.

Melito went so far as to call him "more philanthropic and philosophic" than Antoninus and Hadrian, and set him against the persecuting emperors Domitian and Nero to make the contrast bolder.

“Alone of the emperors,” wrote the historian Herodian, "he gave proof of his learning not by mere words or knowledge of philosophical doctrines but by his blameless character and temperate way of life".

Iain King concludes that Marcus' legacy is tragic, because the emperor's "Stoic philosophy – which is about self-restraint, duty, and respect for others – was so abjectly abandoned by the imperial line he anointed on his death."

While on campaign between 170 and 180, Marcus wrote his Meditations in Greek as a source for his own guidance and self-improvement. The original title of this work, if it had one, is unknown. 'Meditations' – as well as other titles including 'To Himself' – were adopted later.

He had a logical mind and his notes were representative of Stoic philosophy and spirituality. Meditations is still revered as a literary monument to a government of service and duty.

According to Hays, the book was a favourite of Frederick the Great, John Stuart Mill, Matthew Arnold, and Goethe, and is admired by modern figures such as Wen Jiabao and Bill Clinton. It has been considered by many commentators to be one of the greatest works of philosophy.

Meditations survived in the scholarly traditions of the Eastern Church and the first surviving quotes of the book, as well as the first known reference of it by name ('Marcus' writings to himself') are from Arethas of Caesarea in the 10th century and in the Byzantine Suda.

It was first published in 1558 in Zurich by Wilhelm Xylander (ne Holzmann), from a manuscript reportedly lost shortly afterwards. The oldest surviving complete manuscript copy is in the Vatican library and dates to the 14th century.

The Equestrian statue of Marcus Aurelius in the Capitoline Museums

The Column of Marcus Aurelius in Piazza Colonna. The five horizontal slits allow light into the internal spiral staircase.

You have power over your mind - not outside events. Realize this, and you will find strength.

The happiness of your life depends upon the quality of your thoughts.

Waste no more time arguing about what a good man should be. Be one.

— Marcus Aurelius

When you arise in the morning think of what a privilege it is to be alive, to think, to enjoy, to love...

The best revenge is to be unlike him who performed the injury.

— Marcus Aurelius

Accept the things to which fate binds you, and love the people with whom fate brings you together,but do so with all your heart.

It is not death that a man should fear, but he should fear never beginning to live.

— Marcus Aurelius

Never let the future disturb you. You will meet it, if you have to, with the same weapons of reason which today arm you against the present.

― Marcus Aurelius

If someone is able to show me that what I think or do is not right, I will happily change, for I seek the truth, by which no one was ever truly harmed. It is the person who continues in his self-deception and ignorance who is harmed.

― Marcus Aurelius

If it is not right do not do it; if it is not true do not say it.

― Marcus Aurelius

I have often wondered how it is that every man loves himself more than all the rest of men, but yet sets less value on his own opinion of himself than on the opinion of others.

― Marcus Aurelius, Meditations

Whenever you are about to find fault with someone, ask yourself the following question: What fault of mine most nearly resembles the one I am about to criticize?

― Marcus Aurelius

Reject your sense of injury and the injury itself disappears.

― Marcus Aurelius, Meditations

The first rule is to keep an untroubled spirit. The second is to look things in the face and know them for what they are.

― Marcus Aurelius, Meditations

Do not act as if you were going to live ten thousand years. Death hangs over you. While you live, while it is in your power, be good.

― Marcus Aurelius

Begin each day by telling yourself: Today I shall be meeting with interference, ingratitude, insolence, disloyalty, ill-will, and selfishness – all of them due to the offenders’ ignorance of what is good or evil.

― Marcus Aurelius, Meditations

Look well into thyself; there is a source of strength which will always spring up if thou wilt always look.

― Marcus Aurelius, Meditations