PHILOSOPHICAL SOCIETY OF WASHINGTON. 163 



these terms applicable to pretended explanations — having no basis 

 in fact or in reason — proffered in the vain hope of avoiding unex- 

 pected or undesired inductions. But if the phrase be designed to 

 stigmatize either the absolute cause of original properties or their 

 mode of operation, as obscure, hidden, inexplicable, then the epithet 

 is but the expression of a necessary and universal truth, which may 

 be accepted with entire satisfaction. 



On contemplating the backward steps of efficient causation, we' 

 find them not only finite in number, but in any case even surpris- 

 ingly few, — if we neglect the complications of perturbation, and 

 the successions of iteration in time. When we arrive at the prim- 

 itive efficient cause, (if we accept it as ultimate,) this is by admis- 

 sion and very definition — inexplicable ; since any attempt to explain 

 it, necessarily refers it to an antecedent cause, and thus denies it to 

 be ultimate.* Or if this denial be insisted on, then the series of 



must be a scholastic occult quality, or the effect of a miracle. - - - Nor 

 do I find a vacuum established by the reasons of Mr. Newton, or of his 

 partizans, any more than his pretended ' universal gravitation,' or than his 

 'atoms.' No one — unless with very contracted views — can believe either 

 in the vacuum, or in the atoms." 



With equal dignity and cogency, Newton replied to this tirade, in a 

 letter dated February 26, 1716, that he was not to be drawn by M. Leibnitz 

 into a dispute which was nothing to the question in hand. "As for phil- 

 osophy, he colludes in the significations of words, calling those things 

 ' miracles ' which create no wonder ; and those things ' occult qualities ' 

 whose causes are occult, though the qualities themselves be manifest." 

 (Raphson's History of Fluxions. Also the Works of Isaac Newton, edited 

 by Samuel Horsley. 5 vols, quarto. London, 1779-1785: where both let- 

 ters are given: vol. iv, pp. 596, 598.) 



*Says Roger Cotes in his admirable Preface to the Principia: "Since 

 causes naturally recede in a continued chain from the more compounded to 

 the more simple, when the most simple is reached no further backward step 

 is possible. Hence an ultimate cause cannot admit of any mechanical ex- 

 planation ; for if it could, it would by that very fact cease to be ultimate. 

 Will you therefore banish ultimate causes by calling them ' occult?' Then 

 those immediately depending on such must next alike be banished, and 

 straightway those next following ; until relieved from every vestige of a 

 cause, philosophy shall indeed stand purged !" (Newton's Principia. Second 

 edition. 1713. Preface.) 



Says Sir William Hamilton, "As every effect is only produced by the 

 concurrence of at least two causes, and as these concurrent or co-efficient 

 causes in fact constitute the effect, it follows that the lower we descend in 

 the series of causes, the more complex will be the product ; and that the 



