But it is much more important that we succeed in keeping our mental operations in harmony with Nature's laws. And we shall not fall in this if we guard against violent excitement or depression, and if we keep our minds intent on the observance of propriety.
 Marcus Tullius Cicero, On Duties (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Duties
Topic depression excitement
Date 44 BC
Language English
Reference
Note Translated by Walter Miller
Weblink http://www.constitution.org/rom/de_officiis.htm

Context

“{131} We must be careful, too, not to fall into a habit of listless sauntering in our gait, so as to look like carriers in festal processions, or of hurrying too fast, when time presses. If we do this, it puts us out of breath, our looks are changed, our features distorted; and all this is clear evidence of a lack of poise. But it is much more important that we succeed in keeping our mental operations in harmony with Nature's laws. And we shall not fall in this if we guard against violent excitement or depression, and if we keep our minds intent on the observance of propriety. {132} Our mental operations, moreover, are of two kinds: some have to do with thought, others with impulse. Thought is occupied chiefly with the discovery of truth; impulse prompts to action. We must be careful, therefore, to employ our thoughts on themes as elevating as possible and to keep our impulses under the control of reason.
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