426 SCALING LADDER 



and correct the aberrations both of the senses and of the 

 intellect. The consequence is that they, thinking the die 

 finally cast, turn aside to the uncontrolled and fascinating 

 ramblings of genius ; while we, by our different view of the 

 subject, are constrained to enter upon an arduous and -dis 

 tant province, which we unceasingly pray we may admi 

 nister to the advantage and the happiness of mankind. 

 The introductory part of our progress we described in our 

 second book, which, having entered, in the third we treated 

 on the phenomena of the Universe, and on history, plunging 

 into and traversing the woodlands, as it were, of nature, 

 here overshadowed (as by foliage) with the infinite variety 

 of experiments ; there perplexed and entangled (as by thorns 

 and briars) with the subtilty of acute commentations. 



And now, perhaps, by our advance from the woods to 

 the foot of the mountains, we have reached a more disen 

 gaged, but yet a more arduous station. For from history 

 we shall proceed by a firm and sure track, new indeed and 

 hitherto unexplored, to universals. To these paths of con 

 templation, in truth, might appositely be applied the cele 

 brated and often quoted illustration of the &quot; double road of 

 active life,&quot; of which one branch, at first even and level, 

 conducted the traveller to places precipitous and impassable; 

 the other, though steep and rough at the entrance, termi 

 nated in perfect smoothness. In a similar manner, he who, 

 in the very outset of his inquiries lays firm hold of certain 

 fixed principles in the science, and with immoveable reliance 

 upon them disentangles (as he will with little effort) what 

 he handles, if he advances steadily onward, not flinching 

 out of excess either of self-confidence or of self-distrust 

 from the object of his pursuit, will find he is journeying 

 in the first of these two tracks ; and if he can endure to 

 suspend his judgment, and to mount gradually, and to 

 climb by regular succession the height of things, like so 

 many tops of mountains, with persevering and indefatigable 

 patience, he will in due time attain the very uppermost 

 elevations of nature, where his station will be serene, his 

 prospects delightful, and his descent to all the practical 

 arts by a gentle slope, perfectly easy. 



It is therefore our purpose, as in the second book we laid 

 down the precepts of genuine and legitimate disquisition, 

 so in this to propound and establish, with reference to the 

 variety of subjects, illustrative examples ; and that in the 

 form which we think most agreeable to truth, and regard 

 as approved and authorized. Yet we do not alter the cus- 



