the weightiest
scientific questions. There is, however, one motive power in the
world which no man, be he a scientific student or otherwise, can
afford to treat with indifference; and that is, the cultivation of
right relations with his fellow-men--the performance of his duty, not
as an isolated individual, but as a member of society. It is duty in
this aspect, overcoming alike the sense of possible danger and the
desire for repose, that has placed me in your presence here to-night.

To look at his picture as a whole, a painter requires distance; and to
judge of the total scientific achievement of any age, the standpoint
of a succeeding age is desirable. We may, however, transport
ourselves in idea into the future, and thus survey with more or less
completeness the science of our time. We sometimes hear it decried,
and contrasted to its disadvantage with the science of other times. I
do not think that this will be the verdict of posterity. I think, on
the contrary, that posterity will acknowledge that in the history of
science no higher samples of intellectual conquest are recorded than
those which this age has made its own. One of the most salient of
these I propose, with your permission, to make the subject of our
consideration during the coming hour.

It is now generally admitted that the man of to-day is the child and
product of incalculable antecedent time. His physical and
intellectual textures have been woven for him during his passage
through phases of history and forms of existence which lead the mind
back to an abysmal past. One of the qualities which he has derived
from that past is the yearning to let in the light of principles on
the otherwise bewildering flux of phenomena. He has been described by
the German Lichtenberg as 'das rastlose Ursachenthier'--the restless
cause-seeking animal--in whom facts excite a kind of hunger to know
the sources from which they spring. Never, I venture to say, in the
history of the world has this longing been more liberally responded
to, both among men of science and the general public, than during the
last thirty or forty years. I say 'the general public,' because it is
a feature of our time that the man of science no longer limits his
labours to the society of his colleagues and his peers, but shares, as
far as it is possible to share, with the world at large the fruits of
enquiry.

The celebrated Robert Boyle regarded the universe as a machine; Mr.
Carlyle