First follow Nature, and your judgment frame By her just standard, which is still the same: Unerring Nature, still divinely bright, 70 One clear, unchanged, and universal light, Life, force, and beauty, must to all impart, At once the source, and end, and test of Art. Art from that fund each just supply provides, Works without show, and without pomp presides; In some fair body thus the informing soul With spirits feeds, with vigour fills the whole, Each motion guides, and every nerve sustains, Itself unseen, but in the effects, remains. Some, to whom Heaven in wit has been profuse, 80 Want as much more to turn it to its use; For wit and judgment often are at strife, Though meant each other's aid, like man and wife, 'Tis more to guide than spur the Muse's steed, Restrain his fury, than provoke his speed; The wingèd courser, like a generous horse, Shows most true mettle when you check his course. Those rules, of old discover'd, not devised, Are Nature still, but Nature methodised; Nature, like liberty, is but restrain'd 90 By the same laws which first herself ordain'd. Hear how learn'd Greece her useful rules indites, When to repress, and when indulge our flights: High on Parnassus' top her sons she show'd, And pointed out those arduous paths they trod; Held from afar, aloft, the immortal prize, And urged the rest by equal steps to rise. Just precepts thus from great examples given, She drew from them what they derived from Heaven. The generous critic fann'd the poet's fire, 100 And taught the world with reason to admire. Then Criticism the Muse's handmaid proved, To dress her charms, and make her more beloved: But following wits from that intention stray'd, Who could not win the mistress, woo'd the maid; Against the poets their own arms they turn'd, Sure to hate most the men from whom they learn'd. So modern 'pothecaries, taught the art, By doctor's bills to play the doctor's part, Bold in the practice of mistaken rules, 110 Prescribe, apply, and call their masters fools. Some on the leaves of ancient authors prey, Nor time nor moths e'er spoil'd so much as they. Some drily plain, without invention's aid, Write dull receipts how poems may be made. These leave the sense, their learning to display, And those explain the meaning quite away.