an environment.  It would therefore be preferable to combine inertia and attraction in a single formula, expressing the behaviour of bodies towards one another in all their conjunctions, without introducing any inherent forces or absolute measures.  This seems to have been done by Einstein, or at least impressively suggested:  and it has been found that the new calculations correspond to certain delicate observations more accurately than the old.

This revolution in science seems, then, to be perfectly legal, and ought to be welcomed; yet only under one important moral condition, and with a paradoxical result.  The moral condition is that the pride of science should turn into humility, that it should no longer imagine that it is laying bare the intrinsic nature of things.  And the paradoxical result is this:  that the forms of science are optional, like various languages or methods of notation.  One may be more convenient or subtle than another, according to the place, senses, interests, and scope of the explorer; a reform in science may render the old theories antiquated, like the habit of wearing togas, or of going naked; but it cannot render them false, or itself true.  Science, when it is more than the gossip of adventure or of experiment, yields practical assurances couched in symbolic terms, but no ultimate insight:  so that the intellectual vacancy of the expert, which I was deriding, is a sort of warrant of his solidity.  It is rather when the expert prophesies, when he propounds a new philosophy founded on his latest experiments, that we may justly smile at his system, and wait for the next.

Self-knowledge—­and the new science is full of self-knowledge—­is a great liberator:  if perhaps it imposes some retrenchment, essentially it revives courage.  Then at last we see what we are and what we can do.  The spirit can abandon its vain commitments and false pretensions, like a young man free at last to throw off his clothes and run naked along the sands.  Intelligence is never gayer, never surer, than when it is strictly formal, satisfied with the evidence of its materials, as with the lights of jewels, and filled with mounting speculations, as with a sort of laughter.  If all the arts aspire to the condition of music, all the sciences aspire to the condition of mathematics.  Their logic is their spontaneous and intelligible side:  and while they differ from mathematics and from one another in being directed in the first instance upon various unintelligible existing objects, yet as they advance, they unite:  because they are everywhere striving to discover in those miscellaneous objects some intelligible order and method.  And as the emotion of the pure artist, whatever may be his materials, lies in finding in them some formal harmony or imposing it upon them, so the interest of the scientific mind, in so far as it is free and purely intellectual, lies in tracing their formal pattern.  The mathematician can afford to leave to his clients, the engineers, or perhaps the popular philosophers, the emotion of belief:  for himself he keeps the lyrical pleasure of metre and of evolving equations:  and it is a pleasant surprise to him, and an added problem, if he finds that the arts can use his calculations, or that the senses can verify them; much as if a composer found that the sailors could heave better when singing his songs.