Of all the causes which conspire to blind Man's erring judgment, and misguide the mind, What the weak head with strongest bias rules, Is pride, the never-failing vice of fools. Whatever nature has in worth denied,[126] 205 She gives in large recruits of needful pride; For as in bodies, thus in souls, we find What wants in blood and spirits, swelled with wind:[127] Pride, where wit fails, steps in to our defence, And fills up all the mighty void of sense. 210 If once right reason drives that cloud away, Truth breaks upon us with resistless day. Trust not yourself; but your defects to know, Make use of ev'ry friend and ev'ry foe. A little learning is a dang'rous thing; 215 Drink deep, or taste not the Pierian spring:[128] There shallow draughts intoxicate the brain, And drinking largely sobers us again. Fired at first sight with what the muse imparts,[129] In fearless youth we tempt the heights of arts,[130] 220 While from the bounded level of our mind, Short views we take, nor see the lengths behind;[131] But more advanced, behold with strange surprise, New distant scenes of endless science rise! So pleased at first the tow'ring Alps we try,[132] 225 Mount o'er the vales, and seem to tread the sky, Th' eternal snows appear already past, And the first clouds and mountains seem the last: But those attained, we tremble to survey The growing labours of the lengthened way, 230 Th' increasing prospect tires our wand'ring eyes, Hills peep o'er hills, and Alps on Alps arise![133] A perfect judge will read each work of wit[134] With the same spirit that its author writ:[135] Survey the whole, nor seek slight faults to find 235 Where nature moves, and rapture warms the mind; Nor lose for that malignant dull delight, The gen'rous pleasure to be charmed with wit. But in such lays as neither ebb nor flow,[136] Correctly cold,[137] and regularly low, 240 That, shunning faults, one quiet tenour keep, We cannot blame indeed, but we may sleep. In wit, as nature, what affects our hearts Is not th' exactness of peculiar parts; 'Tis not a lip, or eye, we beauty call, 245 But the joint force and full result of all.[138] Thus when we view some well-proportioned dome, (The world's just wonder, and ev'n thine, O Rome![139]) No single parts unequally surprise, All comes united to th' admiring eyes; 250 No monstrous height, or breadth, or length, appear;[140] The whole at once is bold, and regular. Whoever thinks a faultless piece to see, Thinks what ne'er was, nor is, nor e'er shall be.[141]