OF COMMON SENSE. 



427 



pliysical and metaphysical, which we have never derived either from sensa- 

 tion or reflection. 



II. There must therefore exist, somewhere or other in the animal 

 frame, a third percipient principle, from which alone such ideas can have 

 been derived. 



III. From this additional principle there is no appeal: it is higher in its 

 knowledge, and surer in its decision, than either the senses or the reason ; 

 it compels our assent in a variety of cases, in which we should otherwise 

 be left in the most distressing doubt ; and gives us an assurance, not only 

 that there is an external world around us, but that the primary and second- 

 ary qualities of bodies exist equally and uniformly in the bodies themselves, 

 or, in other words, that every thing actually is as it appears to be. 



This mandatory or superior principle is common sense or instinct. 



And in order to ensure himself success in the establishment of the doc- 

 trines contained in this outline, Dr. Reid, with a warmer devotion than falls 

 to the lot of metaphysicians in general, and in some degree breathing of 

 poetic inspiration, opens his Inquiry with the following animated prayer : 

 "Admired philosophy I daughter of light! parent of wisdom and knowledge ! 

 if thou art she ! surely thou hast not yet arisen upon the human mind, nor 

 blessed us with more of thy rays than are sufficient to shed a darkness visi- 

 ble upon the human faculties, and to disturb that repose and security which 

 happier morlals enjoy, who never approached thine altar, nor felt thine 

 influence ! But if, indeed, thou hast not power to dispel those clouds and 

 phantoms which thou hast discovered or created, withdraw this penurious 

 and malignant ray : I despise philosophy, and renounce its guidance : let 

 my soul dwell with common sense," 



How far this petition was attended to, and the prostrate suppliant was 

 enabled to obtain his object, we shall now proceed to examine. 



It is not necessary again to inquire whether the abstruse ideas of exten- 

 sion, figure, and motion, time and space, together with various others of 

 the same kind, can or cannot be derived from mental reflection or external 

 sensation. I have already touched upon the subject, and must refer such 

 of my audience as are desirous of entering into it more deeply to the 

 writings of Locke and Tucker on the one side, and of Reid and Stewart 

 on the other. I shall only observe, in addition, that Mr. Stewart himself 

 admits, with that liberality which peculiarly characterizes his pen, that the 

 ideas or notions of extension and figure, which he somewhat quaintly de- 

 nominates " the mathejnatical affections o/ matter," presuppose the exer- 

 cise of our external senses.* i>ut this being admitted, they ought, if not 

 derived from their immediate action, to be fundamentally dependent upon 

 them. 



Let us step forward at once to an investigation of the newly discovered 

 and sublime principle itself, by which all these [)rorundities are to be fathom- 

 ed, and all the aberrations of sense and reason to be corrected. 



Many of my hearers will perhaps smile at the idea that this high and 

 mighty principle is nothing more than comtnon sense ; but, in truth, the 

 founder and supporters of the northern system seem to have been wofully 

 at a loss, not only what name to give it, but what nature to bestow upon 

 it ; and have hence variously, and at times most cloudily and incongru- 

 ously, described it, and loaded it with as many names and titles as belong 

 to a Spanish grandee or a Persian prime minister. 



♦ Essays, vol. i. p. 95. 



