We cannot observe a 'force'apart from the moving body.Force is one of Bentham's 'fictitious entities,'a word which enables us to state the relations of moving bodies accurately.It harmonises our conceptions.The old belief that all motions stop is not disproved by discovering cases in which force is absent,but by postulating the presence of force wherever we find change of motion.The real proof is not in direct experiment but in the harmonising of an indefinite number of complex statements when once the principle is systematically applied.It can reveal no fact to us,for nothing but experience can show that there are such things as the planets fortunately are,bodies moving freely,so as to illustrate the law continuously.Mill puts the first law of motion on a level with the law that the period of the earth's rotation is uniform.Both 'inductions,'he says,are accurately true.(103)In fact,however,the earth's motion is not absolutely uniform,a truth which we discover by applying the laws of motion,though no direct experiment could exhibit the fact.The law of motion has the authority derived from its rendering possible a consistent interpretation of experiences,whereas the earth's rotation is simply a particular fact which might change if the conditions were altered.The 'law'implies,therefore,a reconstruction of experience not given by simple observation.
This applies to a controversy between Mill and Whewell as to Kepler's great discoveries.They both accept the familiar facts.
Kepler's problem was to show how a simple configuration of the solar system would present the complex appearances which we directly observe.The old observations gave approximately correct statements of the movements of the planets,assuming the earth to be fixed,or,as we may say,neglecting the consideration of its motion.His theory shows how the apparent movements must result if we suppose the sun to be fixed,or rather (as the sun is not really fixed)if we measure from it as fixed.Whewell treats this as a case of 'induction.'It illustrates what he calls the 'colligation of facts'--a happy phrase,accepted by Mill,for the arrangement of facts in a new order,and the application to the facts of the appropriate conceptions;in this case,of the theorems of conic sections and solid geometry.The argument takes the form of a discussion as to whether this should be called induction or an operation subsidiary to induction.(104)Kepler,as Mill urges,was simply describing facts.He discovered a fact in which all the positions of the planet agreed --namely,that they were in an ellipse.If he had been somewhere in space,or the planet had left a visible track,he might have actually seen it to be an ellipse.He had only to 'piece together'his observations,as a man who sails round an island discovers its insularity.The only induction,then,was that as Mars had been in an ellipse he would stay in an ellipse.Apart from the verbal question whether the process be rightly called induction or subsidiary to induction,the real issue is in Mill's complaint that Whewell supposed a 'conception to be something added to the facts.'The conception,Mill admits,is in the mind,but it must be a conception of 'something in the facts.'The ellipse was in the facts before Kepler saw it.He did not put it,but found it there.Whether Kepler's process was inductive or deductive or subsidiary,it was an essential part of scientific investigation.
The man of science must,as Mill truly says,interpret the facts,and nothing but the facts;he must also,as Whewell truly replies,'colligate'or arrange the facts in a new order.The constructive process which justifies me in saying this is an island,or this is an ellipse,is precisely what makes scientific knowledge possible,and involves something more than a mere putting together of raw fact.Every fact,as Whewell sees,may be regarded as a case of countless laws,each of which may be true under appropriate conditions.To eliminate the irrelevant,to organise the whole system of truths,so as to make the order of nature (as Mill forcibly says (105))deducible from the smallest possible number of general propositions,is the aim of science;and Mill obscures this so far as he regards such operations as Kepler's as mere observations of fact,in such a sense as to omit the necessity of a new organisation of the data.
I have gone into some detail in order to show what was the essential characteristic of Mill's doctrine,which was itself,as I have said,an explicit statement of the principles implicitly assumed by his predecessors in the same school.To do him full justice,it would be necessary to show what was the alternative presented by his opponents.The Scottish writers and Whewell brought back 'innate ideas,'or endeavoured to connect knowledge by beliefs and intuitions arbitrarily inserted into the fabric as a kind of supernatural revelation.To explain these intuitive dogmas into effects of 'association'was the natural retort.
Meanwhile the transcendental school was taking the bolder line of rejecting experience altogether,treating it with contempt as a mere rope of sand,and inferring that the universe itself is incarnate logic --a complex web woven out of dialectic,and capable of being evolved from mixing 'is'and 'is not.'To Mill this appeared rightly,as I should say,to be mysticism and ontology,or a chimerical attempt to get rid of the inevitable conditions of all knowledge of reality.The real problem of metaphysics appears to be the discovery of the right method of statement,which will explain what appeared to be the insoluble antithesis between empiricism and intuitionism (to take Mill's phrase),and show that they are attempts to formulate correlative and essential truths.
IX.THE MORAL SCIENCES
