The first requisite for success is the ability to apply your physical and mental energies to one problem incessantly without growing weary.

• The excess of our youth are checks written against our age and they are payable with interest thirty years later.
• To dare to live alone is the rarest courage since there are many who had rather meet their bitterest enemy in the field, than their own hearts in their closet.
• He who studies books alone will know how things ought to be, and he who studies men will know how they are.
• Power will intoxicate the best hearts, as wine the strongest heads. No man is wise enough, nor good enough to be trusted with unlimited power.
• Next to acquiring good friends, the best acquisition is that of good books.
• There are two way of establishing a reputation, one to be praised by honest people and the other to be accused by rogues. It is best, however, to secure the first one, because it will always be accompanied by the latter.
• Examinations are formidable even to the best prepared, for the greatest fool may ask more than the wisest man can answer.
• Those who visit foreign nations, but associate only with their own country-men, change their climate, but not their customs. They see new meridians, but the same men and with heads as empty as their pockets, return home with traveled bodies, but untravelled minds.
• To dare to live alone is the rarest courage since there are many who had rather meet their bitterest enemy in the field, than their own hearts in their closet.
• Physical courage, which despises all danger, will make a man brave in one way and moral courage, which despises all opinion, will make a man brave in another.