My part to-day is to show some of the practical consequences of the impact of science on society. To indicate results, however, without pointing out their causes would be of little value. I hope, therefore, that my colleagues in the papers introductory to these discussions will forgive me if I encroach a few steps on to the domain of principle, allotted to them, in developing my own domain of practice.

In three directions in particular has science exerted an important influence on society : in altering man’s mental outlook, in aiding his physical welfare, and in changing his environment. My comments will follow these paths.

Science and the Mental Outlook of Society.

The most important of the effects of science on the mind of the community, so it appears to me, has been through the example of single-minded search for truth which is the hallmark of all genuine scientific work. The truth to be attained may be limited to a particular plane, with a corresponding restriction in its range of influence ; but within that range the manner of the scientific worker’s approach to the unknown is outstandingly direct and fearless, animated solely by the desire for truth.

But that brings in its train a second reaction on the mental attitude of society. The course of a scientific enquiry would be sadly hampered if the heart were allowed to sway the head. The man of science has to keep his intellect at white heat, but his emotions in cold storage, till the end of his search, when certainly the feelings may be powerfully stirred in the arrival at a satisfying conclusion.