In science, law is not a rule imposed from without, but an expression of an intrinsic process. The laws of the lawgiver are impotent beside the laws of human nature, as to his disillusion many a lawgiver has discovered.

I am sick of diseases, I want to know origins and processes…If we are to prevent disease it is to the beginning of the chain of accumulating stresses that we must look.

It is steadily forgotten that health is a diathesis as much as is scrofula or syphilis and that each of these is a mode of growth.

Thus we work not in the light of public opinion but in the secrecy of the chamber; and perhaps the best of us are apt at times to forget the delicacies and sincerities which under these conditions are essential to harmony and honour.

Students who have attended my [medical] lectures may remember that I try not only to teach them what we know, but also to realise how little this is: in every direction we seem to travel but a very short way before we are brought to a stop; our eyes are opened to see that our path is beset with doubts, and that even our best-made knowledge comes but too soon to an end.

We are led to think of diseases as isolated disturbances in a healthy body, not as the phases of certain periods of bodily development.

Another source of fallacy is the vicious circle of illusions which consists on the one hand of believing what we see, and on the other in seeing what we believe.