6o 



NA TURE 



[November 19, 1891 



be only _^, or 0-5744 times the maximum value of the 



V 3 

 currents in I, Ig, III, III2, V, V.^. Hence the number of 

 convolutions in each of the coils II, II2, IV, IVg, VI, VI2 

 should be :}rds of the number in each of the coils I, I^, 

 III, IIIo, V, V2, and the cross-section of the wire in 

 each of the first 'six coils only i|ths of that in the last six, 

 both of which ratios are symbolically indicated in Fig. 31. 

 By still further following out the same general idea, an 

 alternate current motor with twenty-four, or more, coils 

 on it can be developed, requiring only three main wires to 

 supply the current. And thus, thanks to the labours of 

 Tesla, Bradley, Haselwander, Wenstrom, and last, but 

 by no means least, to the striking ingenuity of Dolivo 

 Doblowolsky, a practical alternate current motor can now 

 be constructed, which will produce as steady a driving 

 force as the best modern direct current motor. 



W. E. A. 

 ( To be continued) 



THE IMPLICATIONS OF SCIENCES 

 I. 



WHEN I was honoured by an invitation to lecture 

 here this evening, I felt much troubled as to the 

 subject which I might most fitly select as my theme. 

 During the forty years I have been a member of the 

 Royal Institution, I have had the privilege of listening to 

 lectures on many very different branches of science, and 

 I know that all branches of science have few or many 

 followers amongst the audience I am now addressing. 



It has struck me, however, that for this single lecture 

 it might be well not to confine myself to any subordinate 

 department of scientific inquiry, but rather to invite your 

 attention to certain questions which deeply concern them 

 all. Thus, it has seemed to me, I might hope to interest 

 a greater number of hearers than it would be possible for 

 me otherwise to do. 



I felt the more encouraged to take this course when I 

 recalled to mind on how many previous occasions I had 

 myself listened to discourses of a similar breadth of 

 scope, given in this theatre by very distinguished men 

 of science. 



Foremost among them I may mention Prof. Huxley, 

 who has here, as elsewhere, called attention to questions 

 which underlie all physical science. I may also refer to 

 that brilliant mathematician, Prof. Clifford, the sad and 

 sudden ending of whose brief career we have good reason 

 to deplore. 



It would be easy to mention the names of other 

 ■scientific celebrities who have here discoursed on matters 

 beyond the scope of any one branch of science. These two, 

 however, will, I think, suffice. 



But before proceeding further I would feign say a few 

 words as to the title of my lecture, so as at once to 

 prevent any misunderstanding as to the object I have in 

 view. 



By " the implications of science^' I mean nothing to 

 which any section of my hearers can object, whatever 

 their notions about "creed" or "conduct" may be. I 

 desire carefully to eliminate all questions of either 

 religion or morals, and I shall confine myself purely and 

 simply to the consideration of certain propositions which 

 appear to me to be latent within, and give force to, what 

 we regard as well-ascertained scientific truths. They are 

 propositions which must, I believe, be assented to by 

 every consistent follower of science, who is convinced 

 that science has brought to our knowledge some truths on 

 which we can, with entire confidence, rely. 



My appeal, then, is to the pure intellect of my hearers, 



' Friday Evening Discourse delivered at the Roj'al Institution by Dr. St. 

 George Mivart, on June 5, 1891. 



NO. I 151, VOL. 45] 



and to nothing else. And indeed I desire to take this 

 opportunity plainly to declare, before this distinguished 

 audience, that not only here and now, but everywhere 

 and always, I unhesitatingly affirm that no system can, or 

 should, stand, which is unable to justify itself to reason. 

 I possess no faculty myself, nor do I believe that any 

 human faculty exists, superior to the intellect, or which 

 has any claim to limit or dominate the intellect's activity. 

 Feelings and sentiments have their undoubted charm 

 and due place in human life, but that place is a sub- 

 ordinate one, and should be under the control of right 

 reason. 



But it is by no means only or mainly against those who 

 would undervalue reason in the interest of sentiment, that 

 I have this evening to protest. My object is to uphold 

 what I believe to be the just claims of our rational nature 

 against all who, from whatever side, or in the name of 

 whatsoever authority, would impugn its sovereign claims 

 upon our reverence, or unduly restrict the area of its 

 sway. 



As I have already intimated, I propose to fulfil this 

 task by calling attention to some half-dozen far-reaching 

 truths implicitly contained in scientific doctrines uni- 

 versally admitted, so that those doctrines cannot logically 

 be maintained, if such implied truths are really and 

 seriously doubted, and still less if they are really dis- 

 believed and denied. These truths, then, are what I 

 mean by " the implications of science." But what is 

 science ? 



The word "science" is now very commonly taken as 

 being synonymous with '■''physical science" There is 

 much to be said against giving the word so narrow a 

 meaning ; nevertheless that meaning will sufficiently 

 serve my purpose this evening. " Science," then, thus 

 understood, is merely ordinary knowledge pursued with 

 extreme care— most careful observation, measuring, 

 weighing, &c. — together with most careful reasoning as 

 to the results of observations and experiments, and also 

 painstaking verification of any anticipations which may 

 have been hazarded. In this way our thoughts are made 

 to conform as accurately as may be with what we regard 

 as the realities they represent. 



The value and the progress of science are unques- 

 tioned. Many foolish discussions are carried on in the 

 world about us ; but certainly no one disputes or doubts 

 the value of science or the fact of its progress. The value 

 of carefully ascertained scientific truths will not at any 

 rate be disputed in this theatre, which has witnessed the 

 triumphs of the immortal Faraday, and which may justly 

 claim to be a very temple of science. And certainly / 

 have no disposition to undervalue it, who have loved it 

 from my earliest years, and devoted such small powers as 

 I possess to its service. I am profoundly convinced that, 

 since I can recollect, biological science has made great 

 progress, and I see grounds for absolute certainty now 

 about many propositions in zoology which were doubtful 

 or undreamed of when I was a lad. 



We all, then, agree that science does advance. Never- 

 theless, it is obvious that such advance would be im- 

 possible if we could not, by observations, experiments, 

 and inferences, become so certain with respect to so7}ie 

 facts as to be able to make them the starting-points for 

 fresh observations and inferences as to other facts. Thus, 

 with respect to the world we live in, most educated men 

 are now certain as to its daily and annual revolutions, as 

 also that its crust is largely composed of sedimentary 

 rocks, containing remains or indications of animals and 

 plants more or less different from those which now live. 

 No one can reasonably deny that we may rely \yith 

 absolute confidence and entire certainty upon a variety 

 of such assertions. 



But our scientific certainties have been acquired more 

 or less laboriously, and a questioning attitude of mind is 

 emphatically the scientific attitude. We ought never to 



