Do the right thing because it is right.

Most men use their knowledge only under guidance from others because they lack the courage to think independently using their own reasoning abilities. It takes intellectual daring to discover the truth.

It is not God's will merely that we should be happy, but that we should make ourselves happy

Physicians think they are doing something for you by labeling what you have as a disease

Beneficence is a duty. He who frequently practices it, and sees his benevolent intentions realized, at length comes really to love him to whom he has done good. When, therefore, it is said, "Thou shalt love thy neighbor as thyself," it is not meant, thou shalt love him first and do him good in consequence of that love, but, thou shalt do good to thy neighbor; and this thy beneficence will engender in thee that love to mankind which is the fulness and consummation of the inclination to do good.

To be beneficent when we can is a duty; and besides this, there are many minds so sympathetically constituted that, without any other motive of vanity or self-interest, they find a pleasure in spreading joy around them, and can take delight in the satisfaction of others so far as it is their own work. But I maintain that in such a case an action of this kind, however proper, however amiable it may be, has nevertheless no true moral worth, but is on a level with other inclinations. . . . For the maxim lacks the moral import, namely, that such actions be done from duty, not from inclination.

All our knowledge begins with the senses, proceeds then to the understanding, and ends with reason. There is nothing higher than reason.