various elements in that system bear to one
another, have long been known. The distance of the sun itself is known
within limits of error relatively speaking not very considerable. Were
the measuring rod we apply to the heavens based on an estimate of the
sun's distance from the earth which was wrong by (say) three per cent.,
it would not to the lay mind seem to affect very materially our view
either of the distribution of the heavenly bodies or of their motions.
And yet this information, this piece of celestial gossip, would seem to
have been the chief astronomical result expected from the successful
prosecution of an investigation in which whole nations have interested
themselves.

But though no one can, I think, pretend that science does not concern
itself, and properly concern itself, with facts which are not to all
appearance illustrations of law, it is undoubtedly true that for those
who desire to extract the greatest pleasure from science, a knowledge,
however elementary, of the leading principles of investigation and the
larger laws of nature, is the acquisition most to be desired. To him who
is not a specialist, a comprehension of the broad outlines of the
universe as it presents itself to his scientific imagination is the
thing most worth striving to attain. But when we turn from science to
what is rather vaguely called history, the same principles of study do
not, I think, altogether apply, and mainly for this reason: that while
the recognition of the reign of law is the chief amongst the pleasures
imparted by science, our inevitable ignorance makes it the least among
the pleasures imparted by history.

It is no doubt true that we are surrounded by advisers who tell us that
all study of the past is barren, except in so far as it enables us to
determine the principles by which the evolution of human societies is
governed. How far such an investigation has been up to the present time
fruitful in results, it would be unkind to inquire. That it will ever
enable us to trace with accuracy the course which States and nations are
destined to pursue in the future, or to account in detail for their
history in the past, I do not in the least believe. We are borne along
like travelers on some unexplored stream. We may know enough of the
general configuration of the globe to be sure that we are making our way
towards the ocean. We may know enough, by experience or theory, of the
laws regulating the flow of liquids, to c