“The competent specialist who has supplemented natural gifts and good judgment by analysis and synthesis can perceive attitudes and proclivities even in the very young, much more readily in those semi-matured, and can with almost infallible certainty point out, not only what work can be undertaken with fair hope of success, but also what slight modification or addition and diminution will more than double the personal power.”

“No law can be sacred to me but that of my nature. Good and bad are but names very readily transferable to that or this; the only right is what is after my constitution; the only wrong is what is against it.”

“I have… begun to collect materials for a work… relating to every department of medical knowledge: …it will be comparatively more concise than these lectures, in proportion to what has been said and written respecting physic, but, I hope, much more complete, with regard to all that is known with certainty, and can be applied with utility.”

“It's a question of attitude. If you really work at something you can do it up to a point. If you really work at being happy you can do it up to a point. But anything more than that you can't. Anything more than that is luck.”

“Marvellous is the power which can be exercised, almost unconsciously, over a company, or an individual, or even upon a crowd by one person gifted with good temper, good digestion, good intellects, and good looks.”

“"There are some dead who are more alive than the living."
"No, no! It would be more true to say that there are some who are more dead than the dead."
"Maybe. In any case there are old things which are still young."
"Then if they are still young we can find them for ourselves…. But I don't believe it. What has been good once never is good again."”

“… if the majority of men cannot know what is good for them, each for himself, how can they know what is good for others by proxy? If they are to be controlled by specialists, how and by what standard can they choose the specialist?”

“Things may be fitting to be done, which are not fitting to be boasted of; for by the perverse judgment of the world, that often becomes the subject of censure, which is, in truth, not only innocent but laudable. What can be more innocent than the indulgence of a natural appetite? Or what more laudable than the propagation of our species?”

“It is an acknowledged fact that we perceive errors in the work of others more readily than in our own.”

“Money does not only help the exchange of goods and services but can also hinder the exchange of goods and services by being kept in the hands of those who have more than they need. Thus it creates a private toll gate where those who have less than they need pay a fee to those who more money than they need.”