SECTION 11. CAUSAL ENQUIRIES. 85 



question. To the immediate and proper perception of the sense, 

 therefore, I do not give much weight; but I contrive that the 

 office of the sense shall be only to judge of the experiment, 

 and that the experiment itself shall judge of the thing." (The 

 Great Instauration, Plan of the Work ; vol. 4, p. 26, of Spedding's 

 edition of Bacon's works.) 



The confusion enveloping the subject of experiment in relation 

 to observation is due, we should remember, to historical causes. 

 The modern idea of scientific observation is the product of a 

 protracted evolution. None of the ancients, not even Lucretius, 

 suspected the complexity of the process. To observe with micro- 

 scopic minuteness, for a prolonged period, under exhaustively 

 varying circumstances of space and other conditions, was only 

 slowly suggested by historic experience, so much so that even 

 now our conception of observation grows in profundity with 

 every decade. Moreover, the instruments which greatly increase 

 our powers of observation are a comparatively recent and still 

 growing acquisition, just as the lack, danger, and impossibility 

 of extensive intercommunication over prodigious distances, nar- 

 rowly limited an enquiry. So with experiment. To Roger Bacon, 

 the idea of appealing to experience appeared to embody a high 

 methodological ideal, and the notion of experiment was scarcely 

 distinguished from experiencing even by Leonardo da Vinci. 1 

 Experience itself had only partially the objective character we 

 attribute to it to-day. Similarly, the modern idea of a scientific 

 experiment has a long history. In Francis Bacon's time it had 

 already developed to no mean degree, as is illustrated by Gil- 

 bert's treatise, De Magneto, and by Galileo's labours generally. 

 And since his day, both on the side of method and of instru- 

 ments, there has been ceaseless improvement. Accordingly, it 

 is futile to examine the subject before us, save in the light of 

 history, in which case the ground is cut beneath the contro- 

 versy, and mutual appreciation follows mutual recrimination. 



SECTION XL CAUSAL ENQUIRIES. 



26. (a) Importance of Causal Enquiries. The object of 

 science is to determine unequivocally the nature and relations 

 of animate and inanimate objects and of psychic phenomena, 

 and one of the most important relations is unquestionably that 

 of cause. Indeed, to know precisely the cause of a phenomenon 

 is to be acquainted precisely with two facts the phenomenon 

 which is the effect and another in so far as it is the cause. 

 Objects of which we do not establish the cause are, as it were, 

 suspended by invisible cords, and the progress of knowledge 

 demands that facts shall not appear isolated. We inquire there- 

 fore into the cause of the cohesion and repulsion of particles 



1 J. V. Marmery, op. cit. 



