Kenneth Clark, Civilisation: A Personal View, 1969.

At certain epochs, man has felt conscious of something about himself - body and spirit - which was outside the day-to-day struggle for existence and the night-to-night struggle with fear; and he has felt the need to develop these qualities of thought and feeling so that they might approach as nearly as possible to an ideal of perfection - reason, justice, physical beauty, all of them in equilibrium. He has managed to satisfy this need in various ways - through myths, through dance and song, through systems of philosophy and through the order that he has imposed upon the visible world.

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It took Gibbon six volumes to describe the decline and fall of the Roman Empire, so I shan't embark on that. But thinking about this almost incredible episode does tell one something about the nature of civilisation. It shows that however complex and solid it seems, it is actually quite fragile. It can be destroyed. 

What are its enemies? Well, first of all fear — fear of war, fear of invasion, fear of plague and famine, that make it simply not worthwhile constructing things, or planting trees or even planning next year’s crops. And fear of the supernatural, which means that you daren’t question anything or change anything. The late antique world was full of meaningless rituals, mystery religions, which destroyed self-confidence. And then exhaustion, the feeling of hopelessness which can overtake people even with a high degree of material prosperity.  There is a poem by the modern Greek poet, Cavafy, in which he imagines the people of an antique town like Alexandria waiting every day for the barbarians to come and sack the city. Finally the barbarians move off somewhere else and the city is saved; but the people are disappointed — it would have been better than nothing. 

Of course, civilisation requires a modicum of material prosperity — What civilization needs:

confidence in the society in which one lives, belief in its philosophy, belief in its laws, and confidence in one’s own mental powers. The way in which the stones of the Pont du Gard are laid is not only a triumph of technical skill, but shows a vigorous belief in law and discipline. Vigour, energy, vitality: all the civilisations—or civilising epochs—have had a weight of energy behind them. 

People sometimes think that civilisation consists in fine sensibilities and good conversations and all that. These can be among the agreeable results of civilisation, but they are not what make a civilisation, and a society can have these amenities and yet be dead and rigid. 

~ Kenneth Clark, Civilisation: A Personal View, 1969. Televised documentary by the BBC, which in our humble opinion, is the greatest such programme ever made.

The School of Athens is one of the most famous frescoes by the Italian Renaissance artist Raphael. It was painted between 1509 and 1511, part of Raphael's commission to decorate the rooms now known as the Stanze di Raffaello, in the Apostolic Palace & St. Peter's Basilica, Vatican City. 

 A key of those depicted:

1: Zeno of Citium 2: Epicurus Possibly, the image of two philosophers, who were typically shown in pairs during the Renaissance: Heraclitus, the "weeping" philosopher, and Democritus, the "laughing" philosopher. 3: unknown (believed to be Raphael), 4: Boethius or Anaximander or Empedocles? 5: Averroes 6: Pythagoras 7: Alcibiades or Alexander the Great? 8: Antisthenes or Xenophon or Timon? 9: Fornarina as a personification of Love or Francesco Maria della Rovere? 10: Aeschines or Xenophon? 11: Parmenides? 12: Socrates 13: Heraclitus 14: Plato 15: Aristotle 16: Diogenes of Sinope 17: Plotinus 18: Euclid or Archimedes with students (Bramante?) 19: Strabo or Zoroaster? 20: Ptolemy? R: Apelles 21: Protogenes.