“ A man who leads a life of tranquillity and reflection, who is not disturbed at home and meddles not with the affairs of the world, may keep his mind at ease and his thoughts in one even course. ”
 Marcus Aurelius, Meditations (c. 170 - 180). copy citation

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“Besides the want of arrangement in the original and of connection among the numerous paragraphs, the corruption of the text, the obscurity of the language and the style, and sometimes perhaps the confusion in the writer's own ideas—besides all this, there is occasionally an apparent contradiction in the emperor's thoughts, as if his principles were sometimes unsettled, as if doubt sometimes clouded his mind. A man who leads a life of tranquillity and reflection, who is not disturbed at home and meddles not with the affairs of the world, may keep his mind at ease and his thoughts in one even course. But such a man has not been tried. All his Ethical philosophy and his passive virtue might turn out to be idle words, if he were once exposed to the rude realities of human existence. Fine thoughts and moral dissertations from men who have not worked and suffered may be read, but they will be forgotten.” source