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.

It is necessary to guard ourselves from thinking that the practice of the scientific method enlarges the powers of the human mind. Nothing is more flatly contradicted by experience than the belief that a man distinguished in one or even more departments of science, is more likely to think sensibly about ordinary affairs than anyone else.

The ordinary patient goes to his doctor because he is in pain or some other discomfort and wants to be comfortable again; he is not in pursuit of the ideal of health in any direct sense. The doctor on the other hand wants to discover the pathological condition and control it if he can. The two are thus to some degree at cross purposes from the first, and unless the affair is brought to an early and happy conclusion this diversion of aims is likely to become more and more serious as the case goes on.

It was not noisy prejudice that caused the work of Mendel to lie dead for thirty years, but the sheer inability of contemporary opinion to distinguish between a new idea and nonsense.

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 mind likes a strange idea as little as the body likes a strange protein and resists it with similar energy. It would not perhaps be too fanciful to say that a new idea is the most quickly acting antigen known to science.

Disease often tells its secrets in a casual parenthesis.