370 ON ANCIENT AND MODERN SKEPTICS. 



world " without form, and void ;" with darkness, not only upon the face of 

 the deep, but there and every where else. 



"That nothing," says Dr. Reid, "can act immediately where it is not, I 

 think must be admitted ; for I think, with Sir Isaac Newton, that power 

 without substance is inconceivable." Lord Kames, however, in his Elements 

 of Criticism, though a strong 1 advocate for the common-sense system, ex- 

 presses his doubts of the doctrine contained in this passage. 



To complete the folly of the age, and fix the laugh of the simple against 

 the wise, while Berkeley, Hume, and Boscovich were thus, in their different 

 ways, dissipating the world of matter, in favour of the world of mind, 

 another set of philosophers started, up, 



i m pios 



Titanas, immanemque turmam,* 



An impious, earih-burn, fierce, Titanic race, 



and put to flight the world of mind in favour of the world of matter. Hobbes, 

 who was a contemporary and friend of Des Cartes, courageously led the van, 

 and did ample justice, and somewhat more than ample justice, to the senses, 

 by contending that we have no other knowledge than what they supply us 

 with, and what they thenvselves derive from the world before them ; that the 

 mind is nothing more than the general result of their action ; and that with 

 them it begins, and with them it ceases. 



To Hobbes succeeded Spinosa, who was born in the very same year with 

 Locke, and who carried forward the crusade of matter against mind, to so 

 illimitable a career, that he made the world, the human senses, the human 

 soul, arid the Deity himself, matter and nothing else : all one common mate- 

 rial being; no part of which can or ever could exist otherwise than as it is, 

 and consequently every part of which is equally the creature and the Creator. 



In the midst of these indiscriminate assaults appeared Hartley, whose 

 learning, benevolence, and piety entitle his memory to be held in veneration by 

 every good man. He strenuously contended for the existence of mind and 

 matter as distinct principles ; and conceived it was in his power to settle the 

 general controversy, by showing what Locke had failed to do, or rather what 

 he had too much modesty to attempt, the direct means by which the external 

 senses, and consequently the external world, operate upon the mind. And 

 hence arose the well-known and at one time highly popular hypothesis of 

 the association of ideas. It was conceived by Dr. Hartley that the nervous 

 fibrils, which form the medium of communication between the external 

 senses and the brain or sensory, are solid and elastic capillaments, that on 

 every impression of objects upon the senses the nervous chord, immediately 

 connected with the sense, vibrates through its whole length, and commu- 

 nicates the vibration to the substance of the brain, and particularly to its 

 central region, which is the seat of sensation, leaving upon every commu- 

 nication a mark or vestige of itself; which produces a sensation, and excites 

 its correspondent perception or idea. The more frequently these vibrations 

 are renewed, or the more vigorously they are impressed, the stronger will 

 be the vestiges or ideas they induce ; and as, in every instance, they occasion 

 vibratiuncles, or miniature vibrations, through the' substance of the brain 

 itself, a foundation is hereby laid for a series of slighter vestiges, sensations, 

 and ideas after the primary vibrations have ceased to act. And hence ori- 

 ginate the faculties of memory and imagination. And as any order of vibra- 

 tions, by being associated together a certain number of times, obtain a habit 

 of mutual influence, arty single sensation or single idea belonging to such 

 order acquires a power of calling the whole train into action, either synchro- 

 nously or successively, whenever called into action itself. 



Now, according to this system, the brain of man is a direct sensitive violin, 

 consisting- of musical strings, whose tones go off in thirds, fifths, and eighths, 



Hor. lib. iii. 4. 



