Sole judge of truth, in endless error hurl'd;
The glory, jest, and riddle of the world!

Go, wondrous creature! mount where science guides; Go, measure earth, weigh air, and state the tides; Instruct the planets in what orbs to run, Correct old time, and regulate the sun; Go, soar with Plato to the' empyreal sphere, To the first good, first perfect, and first fair; Or tread the mazy round his followers trod, And, quitting sense, call imitating God; As eastern priests in giddy circles run, And turn their heads to imitate the sun, Go, teach Eternal Wisdom how to rule Then drop into thyself, and be a fool!

Superior beings, when of late they saw A mortal man unfold all Nature's law, Admir'd such wisdom in an earthly shape, And show'd a Newton as we show an ape. Could He, whose rules the rapid comet bind, Describe or fix one movement of his mind? Who saw its fires here rise, and there descend, Explain his own beginning or his end? Alas! what wonder! man's superior part Uncheck'd may rise, and climb from art to art; But when his own great work is but begun, What reason weaves by passion is undone. Trace science then, with modesty thy guide: First strip off all her equipage of pride; Deduct what is but vanity or dress,

Or learning's luxury, or idleness;

Or tricks to show the stretch of human brain,
Mere curious pleasure, or ingenious pain;
Expunge the whole, or lop the' excrescent parts
Of all our vices have created arts;

Then see how little the remaining sum,

Which serv'd the past, and must the times to come! 2. Two principles in human nature reign, Self-love to urge, and reason to restrain;

Nor this a good, nor that a bad we call,
Each works its end, to move or govern all ;
And to their proper operation still

Ascribe all good, to their improper-ill.

Self-love, the spring of motion, acts the soul; Reason's comparing balance rules the whole. Man but for that no action could attend, And but for this were active to no end; Fix'd like a plant on his peculiar spot, To draw nutrition, propagate, and rot; Or, meteor-like, flame lawless through the void, Destroying others, by himself destroy'd.

Most strength the moving principle requires ;
Active its task, it prompts, impels, inspires.
Sedate and quiet the comparing lies,

Form'd but to check, deliberate, and advise.
Self-love, still stronger, as its object's nigh,
Reasons at distance, and in prospect lie:
That sees immediate good by present sense;
Reason the future and the consequence.
Thicker than arguments temptations throng;
At best more watchful this, but that more strong.
The action of the stronger to suspend,

Reason still use, to reason still attend.

Attention habit and experience gains ;

Each strengthens reason, and self-love restrains.
Let subtle schoolmen teach these friends to fight,
More studious to divide than to unite ;

And grace and virtue, sense and reason split,
With all the rash dexterity of wit.

Wits, just like fools, at war about a name,
Have full as oft no meaning, or the same.
Self-love and reason to one end aspire,
Pain their aversion, pleasure their desire;
But greedy that, its object would devour;
This taste the honey, and not wound the flow'r :
Pleasure, or wrong or rightly understood,
Our greatest evil or our greatest good.

3. Modes of self-love the passions we may call; Tis real good or seeming moves them all : But since not every good we can divide, And reason bids us for our own provide, Passions, though selfish, if their means be fair, List under reason, and deserve her care; Those that imparted court a nobler aim, Exalt their kind, and take some virtue's name. In lazy apathy let stoics boast

Their virtue fix'd; 'tis fix'd as in a frost; Contracted all, retiring to the breast; But strength of mind is exercise, not rest; The rising tempest puts in act the soul, Parts it may ravage, but preserves the whole. On life's vast ocean diversely we sail, Reason the card, but passion is the gale; Nor God alone in the still calm we find, He mounts the storm, and walks upon the wind. Passions, like elements, though born to fight, Yet, mix'd and soften'd, in his work unite: These 'tis enough to temper and employ; But what composes man can man destroy? Suffice that reason keep to nature's road; Subject, compound them, follow her and God. Love, hope, and joy, fair pleasure's smiling train, Hate, fear, and grief, the family of pain.

These mix'd with art, and to due bounds confin'd, Make and maintain the balance of the mind; The lights and shades, whose well-accorded strife Gives all the strength and colour of our life. Pleasures are ever in our hands or eyes, And when in act they cease, in prospect rise; Present to grasp, and future still to find, The whole employ of body and of mind. All spread their charms, but charm not all alike; On different senses different objects strike: Hence different passions more or less inflame, As strong or weak the organs of the frame; And hence one master-passion in the breast, Like Aaron's serpent, swallows up the rest. As man, perhaps, the moment of his breath Receives the lurking principle of death,

The young disease, that must subdue at length,
Grows with his growth,and strengthens with his strength:
So, cast and mingled with his very frame,

The mind's disease, its ruling passion came;
Each vital humour, which should feed the whole,
Soon flows to this in body and in soul;
Whatever warms the heart or fills the head,
As the mind opens, and its functions spread,
Imagination plies her dangerous art,
And pours it all upon the peccant part.
Nature, its mother, habit is its nurse;
Wit, spirit, faculties, but make it worse;
Reason itself but gives it edge and pow'r,
As Heav'n's blest beam turns vinegar more sour.
We, wretched subjects, though to lawful sway,
In this weak queen, some favourite still obey:
Ah! if she lend not arms as well as rules,
What can she more than tell us we are fools?
Teach us to mourn our nature, not to mend,
A sharp accuser, but a helpless friend!
Or from a judge turn pleader, to persuade
The choice we make, or justify it made;
Proud of an easy conquest all along,

She but removes weak passions for the strong:
So when small humours gather to a gout,
The doctor fancies he has driv'n them out.

Yes, nature's road must ever be preferr'd;
Reason is here no guide, but still a guard;
'Tis her's to rectify, not overthrow,
And treat this passion more as friend than foe:
A mightier pow'r the strong direction sends,
And several men impels to several ends:
Like varying winds, by other passions tost,
This drives them constant to a certain coast.
Let pow'r or knowledge, gold or glory, please,
Or (oft more strong than all) the love of ease;
Through life 'tis follow'd, ev'n at life's expence ;
The merchant's toil, the sage's indolence,
The monk's humility, the hero's pride,
All, all alike, find reason on their side.

The' eternal art educing good from ill, Grafts on this passion our best principle: Tis thus the mercury of man is fix'd,

Strong grows the virtue with his nature mix'd;
The dross cements what else were too refin'd,
And in one interest body acts with mind.
As fruits ungrateful to the planter's care,
On savage stocks inserted, learn to bear;
The surest virtues thus from passions shoot,
Wild nature's vigour working at the root.
What crops of wit and honesty appear.
From spleen, from obstinacy, hate, or fear!
See anger zeal and fortitude supply;
Ev'n avarice prudence, sloth philosophy;
Lust, through some certain strainers well refin'd,
Is gentle love, and charms all womankind;
Envy, to which the' ignoble mind's a slave,
Is emulation in the learn'd or brave;

Nor virtue male or female can we name,

But what will grow on pride or grow on shame. Thus nature gives us (let it check our pride) The virtue nearest to our vice allied: Reason the bias turns to good from ill, And Nero reigns a Titus if he will. The fiery soul abhorr'd in Catiline, In Decius charms, in Curtius is divine: The same ambition can destroy or save, And makes a patriot as it makes a knave. 4. This light and darkness in our chaos join'd, What shall divide ?-the God within the mind, Extremes in nature equal ends produce; In man they join to some mysterious use; Though each by turns the other's bounds invade, As in some well-wrought picture light and shade, And oft so mix, the difference is too nice Where ends the virtue or begins the vice. Fools! who from hence into the notion fall "That vice or virtue there is none at all. If white and black blend, soften, and unite A thousand ways, is there no black or white?