An event experienced is an event perceived, digested, and assimilated into the substance of our being, and the ratio between the number of cases seen and the number of cases assimilated is the measure of experience.

If we watch ourselves honestly we shall often find that we have begun to argue against a new idea even before it has been completely stated.

The fundamental activity of medical science is to determine the ultimate causation of disease.

The dispassionate intellect, the open mind, the unprejudiced observer, exist in an exact sense only in a sort of intellectualist folk-lore; states even approaching them cannot be reached without a moral and emotional effort most of us cannot or will not make.

The truly scientific mind is altogether unafraid of the new, and while having no mercy for ideas which have served their turn or shown their uselessness, it will not grudge to any unfamiliar conception its moment of full and friendly attention, hoping to expand rather than to minimize what small core of usefulness it may happen to contain.

It is sometimes asserted that a surgical operation is or should be a work of art ... fit to rank with those of the painter or sculptor. ... That proposition does not admit of discussion. It is a product of the intellectual innocence which I think we surgeons may fairly claim to possess, and which is happily not inconsistent with a quite adequate worldly wisdom.

If mankind is to profit freely from the small and sporadic crop of the heroically gifted it produces, it will have to cultivate the delicate art of handling ideas. Psychology is now able to tell us with reasonable assurance that the most influential obstacle to freedom of thought and to new ideas is fear; and fear which can with inimitable art disguise itself as caution, or sanity, or reasoned skepticism, or on occasion even as courage.