Mbh 5.34.2a

“Vidura said, ‘Even if unasked, one should speak truly, whether his words be good or bad, hateful or pleasing, unto him whose defeat one doth not wish. I shall, therefore, say, O king, what is for the good of the Kurus. I shall say what is both beneficial and consistent with morality. Listen to me. Do not, O Bharata, set the heart upon means of success that are unjust and improper. A man of intelligence must not grieve if any purpose of his doth not succeed, notwithstanding the application of fair and proper means. Before one engageth in an act, one should consider the competence of the agent, the nature of the act itself, and its purpose, for all acts are dependent on these. Considering these one should begin an act, and not take it up on a sudden impulse. He that is wise should either do an act or desist from it fully considering his own ability, the nature of the act, and the consequence also of success. The king who knoweth not proportion or measure as regards territory, gain, loss, treasury, population, and punishment, cannot retain his kingdom long. He, on the other hand, who is acquainted with the measures of these as prescribed in treatises, being necessarily possessed of the knowledge of religion and profit, can retain his kingdom. As the stars are affected by the planets, so is this world affected by the senses, when they are directed, uncontrolled, to their respective objects. Like the moon during the lighted fortnight, calamities increase in respect of him who is vanquished by the five senses in their natural state, which ever lead him towards various acts. He who wisheth to control his counsellors before controlling his own self, or to subdue his adversaries before controlling his counsellors, at last succumbs deprived of strength. He, therefore, who first subdueth his own self regarding it as a foe, never faileth to subdue his counsellors and adversaries at last.