And mark that point where sense and dulness meet.

Nature to all things fix'd the limits fit,
And wisely curb'd proud man's pretending wit.
As on the land while here the ocean gains,
In other parts it leaves wide sandy plains;
Thus in the soul while memory prevails,
The solid power of understanding fails;
Where beams of warm imagination play,
The memory's soft figures melt away.
One science only will one genius fit, 60
So vast is art, so narrow human wit:
Not only bounded to peculiar arts,
But oft in those confined to single parts.
Like kings, we lose the conquests gain'd before,
By vain ambition still to make them more;
Each might his several province well command,
Would all but stoop to what they understand.

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,