Sophie's World: A Novel About the History of Philosophy

Heraclitus pointed out that the world is characterized by opposites. If we were never ill, we would not know what it was to be well. If we never knew hunger, we would take no pleasure in being full. If there were never any war, we would not appreciate peace. And if there were no winter, we would never see the spring.

You can’t experience being alive without realizing that you have to die, she thought. But it’s just as impossible to realize you have to die without thinking how incredibly amazing it is to be alive.

A number of philosophers held that we have absolutely nothing in the mind that we have not experienced through the senses. A view such as this is called empiricism

Descartes, and he was followed by Spinoza and Leibniz, Locke and Berkeley, Hume and Kant.

If he is indeed infinite, he must be present in everything. This idea is called pantheism.

The economy was now characterized by feudalism, which meant that a few powerful nobles owned the land, which the serfs had to toil on in order to live.

The word 'medieval' is used negatively nowadays about anything that is over-authoritative and inflexible. But many historians now consider the Middle Ages to have been a thousand-year period of germination and growth. The school system, for instance, was developed in the Middle Ages. The first convent schools were opened quite early on in the period, and cathedral schools followed in the twelfth century. Around the year 1200 the first universities were founded, and the subjects to be studied were grouped into various 'faculties,' just as they are today."

By Indo-European we mean all the nations and cultures that use Indo-European languages.

Mysticism

A mystical experience is an experience of merging with God or the "cosmic spirit." Many religions emphasize the gulf between God and Creation, but the mystic experiences no such gulf. He or she has experienced being "one with God" or "merging" with Him

The most important figure in Neoplatonism was Plotinus (c. 205-270), who studied philosophy in Alexandria but later settled in Rome.