Jdlt 31, 1885.] 



KNO^A/LEDGE ♦ 



oanse and the nature of legitimate assumption. The fact of de- 

 velopment itself, which is as certain as the tlieorj' of gravitation, 

 does not appear, on the whole, to be directly attacked. (Mr. Charles 

 E. Bell, in his excellent letter [1814], coulirms my opinion as to 

 the difficulty of making out " Commentator's" meaning.) 



I. The real cause of any phenomenon is properly the tout ensemlle 

 of the conditions necessary to bring it about. But we seldom use 

 the word " cause " in this sense ; nor do we generally speak of the 

 permanent essential properties of bodies as the cause of phenomena, 

 although, in fact, they are necessary conditions ; e.;;., we never say 

 that it is the strengtli of the boiler-plates that drives the steam, 

 engine. In speaking of cause we use the term mostly with re- 

 ference to an antecedent, which, being introduced into a group of 

 more or less permanent conditions, a certain consequent invariably 

 follows it. 



Further, there arc proximate causes and ultimate causes ; the 

 ultimate or final cause of all, we can, of course, never understand. 



"Commentator's" difficulties obviously originate in not discri- 

 minating the various kinds of causes. Natural selection is one of 

 the proximate causes of evolution. The inherent potentialities of 

 the organism, including " the million-timos-proved-fact of varia- 

 bility," may be considered as a more or less permanent group of 

 conditions, into which the antecedent, viz., natural selection being 

 introduced, the consequent, viz., development results under certain 

 circumstances. No doubt the organism has a power of adjusting 

 itself to its environment, and by mutual interaction a modification 

 of the organism takes place. Darwin probably did not give so 

 much prominence to this fact aa some of his followers, e.rj., Mr. S. 

 Butler ; but the fact, so far from being opposed to natural selection, 

 is rather complementary to it; nature selects the fit — the fitness 

 may have been acquired, so to say, accidentally or by adjustment^ 

 and kills off the unfit. But, indeed, adjnstment is implied in the 

 very conception of life. H. Spencer defines life as " the continuous 

 adjustment of internal relations toexternal relations." It is, there- 

 fore, quite legitimate to say that natural selection is a cause of 



"Commentator" appears in certain passages to insist on the 

 inherent potentiality of the organism as the sole cause of develop- 

 ment. It is certainly a condition of evolution, and is the unusual 

 case in which the tout ensemble of the conditions is regarded as the 

 cause ; the inherent potentiality necessarily forms part of the cause. 

 But what do we gain by talking in the vague language of which 

 " Commentator " is so fond, about " predestined development," the 

 " I am," &o., if we know nothing of the mode of operation of such 

 forces ? We have only, in another form, the celebrated explanation 

 of opium causing sleep because it possesses soporific qualities. To 

 say that organisms possess evolutionary energy, and, therefore, 

 they develop, explains nothing. And "Commentator" himself is 

 not quite satisfied with thus settling the matter, for he still calls 

 out for " the cause, the cause," failing to distinguish causes that 

 can bo known from the final cause, which, as our knowledge is 

 relative, must ever remain unknown to us. Darwin has shown us 

 certain proximate causes of development, and others have further 

 elucidated the subject. Why, then, should we despise causes that 

 can be known, aa '' Commentator" would have us do, because wo 

 cannot reach the ultimate cause ? It is as vain to cry after the 

 final " cause, the cause, my soul," as for a baby to cry after the 

 moon. We may well console ourselves when we compare the 

 knowledge of the present day with that of former times. 



" Ea ist ein gross Ergotzen, 

 Sich in den (ieist der Zeiten zu versetzen, 

 Zu schauen, wio vor una eiu weiser Maun gedacht, 

 Und wio wir's dann zuletzt so herrlich weit gebracht." 



II. "Commentator" and "Gamma" [170G] appear to have but 

 vague notiona as to the nature of legitimate and illegitimate 

 assumptions. J. S. Mill writes as foUowa with reference to 

 hypothesia : — 



" It appears, then, to be a condition of a genuinely scientific 

 hypothesia that it be not destined always to remain as hypothesis, 

 but be of such a nature aa to bo either proved or disproved by that 

 comparison with observed facta which is termed verification. . . . 

 I conceive it to be necessury, when the hypothesis relates to 

 causation, that the supposoil r.iu^i' slmulil not only bo a real phe- 

 nomenon, something aclnallv i i-'inv in Tiature, but should bo 

 already known to exercise, M, ;,; i ,,,■ i . ,■ ipablo of exercising, an 



autli I 0,111 Ml!! 'n„. iM!!,,wiHg ia the first of the celebrated 

 " Ki 1 ,' 11 ': ' ('fnisa« rerum materialism non 



l m / ,1 ,» 1 ct verx sint, et earum phanomenis 



3 the n 



mpti 



a of natural aeloo- 

 T. Common'. 



THE STILL SMALL VOICE FROM THE FOSSIL GREAT 

 DEEP. 



[1841]— Marvellous ! this tiny " note of preparation" — as it were 

 like the entrance of "the Son of God " into the world — the first 

 appearance, amid all those unspeakable monster forms and giant- 

 lives of the Triassic and Jurassic epochs, of mammalian lite— the 

 first relics of small marsupial animals, " allied to the Myrmecobins 

 or Banded Ant-eater of New South Wales" (Geikie). 



How did they come there ?—" that is the question ! " 



Does not this confirm what was lately suggested: — "is it not 

 monstrous to hypothesize ? yon cat, suckliiig her kittens, was 

 evolved out of yon pigeon in the chest beside her, pumping maize 

 into her voung! " 



Horrifi'e saurians, and bird-like reptiles (or reptilian birds) were 

 the full-grown companions of these tiny marsupials. No wildest 

 dogmatist of the Darwinian school would maintain that these 

 charming creatures were lineally begotten of the Dinosaurs, 

 Gnaliosaurs, Pterosaurs !— he must, therefore, de novo, fall back 

 upon his ever-ready, all-too-convenient. Common Progenitor. 



Now, I do submit, that the theory which maintains, the Saurs 

 and these bijou marsupials were evolved from one and the same 

 protoplasm demands rhadaraanthine scrutiny, indeed ; ia bounden 

 to furnish at least a scrap of proof. 



With reference to Dr. Geikie'a work, learned and laboriotiB 

 though it be, I cannot refrain from here entering a small protest. 

 I never knew a book more greeted with flourish of trumpets, yet I 

 find Hugh Miller— Scotia's happier Burns; with that heaven-born 

 style, that aroma of fragrance lavishing (yet continently) more 

 genius in one of liia chapters than the Bigwigs in one of their books 

 — Hugh Miller does not appear to be mentioned, mirabile dicfu ! in 

 Dr. Geikie's chapter on the Old Bed Sandstone; the Old Red! 

 Hugh Miller's formation ! he who discovered the Pterichthys, and 

 whose honoured name Agassiz gave to that fossil (Pterichthys 

 MOleri, "the Old Bed Sandstone," p. 82— a prose poem if ever 

 there was one) ; but Dr. Geikie does not give.* 



The sketch too, of " Vesuvius from the sea" is so unlike that 

 I did not recognise the mountain j though I have dwelt near it 

 almost ten years. Alexaxdeb Teeigen. 



Ana Capri, Italy. 



OCULAR SPECTRA. 

 [18-12]— What on earth does Mr. Cave Tliomasmean in letter 1815 

 when he writes : " The important fact that the ocular spectra have 

 no external existence whatever does not as yet appear to be fully 

 recognised ? " Does he mean the ocular spectra are like Mahomet's 

 coffin, suspended in mid Pjiace, acted on by neither the laws of 

 gravity nor the rules of Fpiritland r Surely tho fact ia about as 

 important as the fact that when I have a pain in my stomach I 

 cannot show the doctor where it is, but when I cut my finger I can. 

 Does Mr. Cave Thomas argue that because wo see the sun above 

 the horizon for a few minutes after it has set that what we see has 



. of sunlight by the coloured figur 



Jos. W. ALESANDt 



THINGS IN GENERAL, AND A FEW OTHER SUBJECTS. 



" To speak of many things ; 

 Of shoes, and shii).s, and sealing-wax, 

 And cabbages and kings, 



[• Tlie only meuliou of Hugh 1 

 Geikie's book is on p. 277. — Ed.J 



