218 



♦ KNOWLEDGE 



[August 1, 1887. 



science has ever even begun to apply the true Baconian 

 method — unless, indeed, we consider Bacon himself as one 

 who tried the method, laying himself open to the well- 

 merited stroke of the great deductive (or rather, deductively 

 inductive) philosopher Harvey, who said to him : " Bacon 

 writes philosophy like a Lord Chancellor." Any one who 

 wishes to see what utter nonsense may be deduced by one 

 attempting to apply the true Baconian method of induction 

 should read Bacon's discussion of heat in the second book of 

 the " Novum Organum." The gathering of instances is full of 

 mistakes such as even in his day should have been impos- 

 sible ; their classification and comparison introduces the 

 wildest and most fanciful notions : the " vintage " is worthy 

 of the bad fruit and the poor classification. After thirty or 

 forty closely printed pages of misapprehended facts and 

 delusive reasoning. Bacon arrives at this noteworthy con- 

 clusion : — 



" Heat is an expansive motion restrained, and striving to 

 exert itself in the smaller particles : the expansion is 

 modified by its tendency to rise, through expanding 

 towards the exterior, and the effort is modified by its not 

 being sluggish, but active and somewhat violent." 



Of course, those who can find Harvey's discovery of the 

 circulation of the blood and the Copernican theory of the 

 solar system in Shakespeare may very well imagine that 

 Bacon's definition of heat as an " expansive motion restrained " 

 was a splendid anticipation of the modern theory that " heat 

 is a mode of motion." In reality the modern theory of 

 heat would be just as certainly and absolutely negatived if 

 Bacon's imagined facts were real ones, or if his definition of 

 heat as above quoted were sound, as the Copernican theory 

 would be negatived if the ideas expressed by Ulysses in 

 " Troilus and Cressida " were just, and as the circulation of 

 the blood would be disproved if the account of the office of 

 the blood given by Menenius Agrippa in the first scene of 

 " Coriolanus " were correct. The poor " vintage " resulting 

 from Bacon's discussion of heat is as much like the theory 

 based on the researches of Ampere, Laplace, JMayer, Magnus, 

 Joule, Eumford, and the rest, as bad vinegar is like the best 

 Burgundy, or the dregs of a bottle of British "gooseberry " 

 like a freshly poured glass of Veuve Clicquot. Not even 

 the very beginnings of the modern science of heat can be 

 traced in Bacon's definition ; the laws of convection, con- 

 duction, and radiation of heat are as utterly absent as the 

 more advanced developments of the science — • Provost's 

 theory of exchanges, the laws of specific heat, the kinship 

 between heat, light, electricity, and chemical action, and the 

 like. The very circumstance that the modern theory of 

 heat can be imagined to exist vmder Bacon's definition is the 

 best proof of the worthlessness of a definition which is so 

 vague that any theory of heat whatever might have been 

 equally well supposed (by the ill-informed) to undei'lie it. 



It may be interesting to compare with Bacon's attempt 

 to employ his own system efiectively such scientific dis- 

 coveries as Newton, Harvey, or Darwin have achieved by 

 that combination of deductive and inductive methods which 

 alone has led to any real progress in science from the days 

 of the science students of Babylon, Egypt, and India to the 

 present time. I take the work of Newton as that which 

 falls most fully within my own range of study, and in deal- 

 ing with which I can best recognise how much or how little 

 Bacon had to do with the result achieved. 



To begin with, note that the discovery of the law of gravity 

 was the culmination of a series of discoveries. 



To go no farther back than the time of Copernicus, it is 

 evident that we have in the Copernican theory a necessary 

 predecessor of the theory of gravity. That Copernicus died 

 Boventeen years before Bacon was born aflfords, as I have 

 already suggested, a tolerably clear proof that the Baconian 



method was not essential to the achievement of great scien- 

 tific discoveries. Vixere fortes ante Agaiiiernnona multi — 

 there were many strong men before Agamemnon, many 

 great thinkers before Newton. The Copernican theory was 

 established by that fruitful combination of deduction and 

 induction to which I have just referred — induction having 

 had a somewhat larger share than usual in the work, since 

 undoubtedly astronomical observations were carried on 

 much longer than they need have been before analysis was 

 applied to the evidenc3 collected and its true meaning de- 

 duced. Here was proof, before Bacon described his method, 

 of its worthlessness ; for all the multitudinous obsei'vationa 

 of the planets before Copernicus's time had led only to 

 greater and greater perplexity and confusion worse con- 

 founded, " ceutrics and eccentrics, scribbled o'er cycle and 

 epicycle, orb in orb." But, oddly enough. Bacon himself 

 has shown how valueless his method was l)y which the mere 

 multiplying of observations was to be trusted for the educing 

 of new truths. For though, as Mr. Ellis (one of the few 

 competent men of science who has ever dealt with Bacon's 

 claims) points out, " Bacon paid great attention to astronomy, 

 discussed carefully the methods in which it ought to be 

 studied, and constructed for the satisfaction of his own 

 mind an elaborate theory of the heavens," his theory was 

 purely Ptolemaic and altogether erroneous. 



If the theory of Copernicus, while based on an exceptional 

 amount of inductive evidence, was nevertheless a triumph 

 of the deductive method, the work of Kepler was excep- 

 tionally, and indeed unduly, deductive. He was not willing 

 to examine facts with suflicient patience before conceiving 

 theories, but with amazing liveliness of imagination con- 

 ceived theory after theory and then sought for facts whereby 

 to test them. If he had not been controlled by singular 

 self-restraint, leading him to submit his favoured fancies to 

 the test of observation, and to give them up one after the 

 other as observation decided against them, Kepler would 

 have achieved no success. But fortunately his self-restraint 

 in this respect was as remarkable as his freedom from all 

 restraint in theorising. Nothing seemed more incautious 

 than his theorising ; but then nothing could have been more 

 cautious than his investigation of his theories, or more 

 thorough than the tests to which he subjected them. 



Galileo was a disciple of the sounder scientific school. 

 His laboui's, quite as necessary precui-sors of Newton's work 

 on the physical side as Kepler's on the astronomical, were 

 conducted on the truest principles. All his theories were 

 suggested by observation (not one of Kepler's was), and they 

 were all in turn tested by observation. The operation of 

 terrestrial gravity in particular (despite the nonsensical story 

 of Newton and the apple) was thoroughly mastered by 

 Galileo, applying throughout the method of scientific 

 research by which all the scientific discoveries of modern 

 times have been effected. Assuredly Galileo borrowed 

 nothing from his contemporary, the English Lord Chancellor. 



When the way had been duly prepared, Newton entered 

 on his great task. Let us consider what he did, and how he 

 did it. A philosopher of the true Baconian type, Flamsteed, 

 the Astronomer-Royal, was collecting at Greenwich multi- 

 tudinous observations of the heavenly bodies — a work which 

 might have gone on, even as the modern meteorological 

 observations at Greenwich and elsewhere have gone on, till 

 millions of observed facts had been collected and nothing 

 learned. Newton, who knew that the planets move accord- 

 ing to certain laws around the sun, and the moon — not 

 I'ecognisably under the same laws — round the earth, and 

 further, that bodies are drawn towards the earth by the 

 force of terrestrial gravity, was led — not by Flamsteed's 

 collection of facts, not by gathered facts at all, but by a 

 happy thought based on pre-established theories — to inquire 



