Or whether doth my mind, being crown’d with you,
Drink up the monarch’s plague, this flattery?
Or whether shall I say, mine eye saith true,
And that your love taught it this alchemy,
To make of monsters and things indigest
Such cherubins as your sweet self resemble,
Creating every bad a perfect best,
As fast as objects to his beams assemble?
O! ’tis the first, ’tis flattery in my seeing,
And my great mind most kingly drinks it up:
Mine eye well knows what with his gust is ’greeing,
And to his palate doth prepare the cup:
If it be poison’d, ’tis the lesser sin
That mine eye loves it and doth first begin.
In plain English
The speaker asks himself a hard question: is his mind—crowned and elevated by the young man—simply gulping down flattery like a monarch poisoned by his own courtiers? Or should he trust what his eye tells him: that the young man's love has taught him a kind of magic, one that transforms even ugly, shapeless things into beautiful cherubs resembling the young man himself?
He answers his own question: it's flattery, pure and simple. His mind drinks it down royally. His eye knows exactly what it wants to see, and it eagerly prepares that vision like a cup for his palate to taste. The speaker admits the guilt but shifts the blame: if this vision is poison, at least his eye loved it first—the eye is the real culprit, not the mind that follows.
There's a dark wit here. He's not denying that he sees the young man through rose-tinted glass; he's confessing it. But he's also suggesting that the eye—perception itself—is the guilty party, the seducer, leaving the mind merely complicit in drinking what's offered.
