A pretty bad piece of verse, but...

Love not me for comely grace,
For my pleasing eye or face,
Nor for any outward part,
No, nor for a constant heart:
For these may fail or turn to ill,
So thou and I shall sever:
Keep, therefore, a true woman's eye,
And love me still but know not why—
So hast thou the same reason still
To doat upon me ever!

- Anonymous (1609)

For some reason I was thinking about how difficult it is to dance the tango of seduction, and I started to miss those rare rare rare occassions when it happens effortlessly. At the time you suspect that something must not be right, and so you take it a bit for granted; but it's such a vacation when all the insanity of love falls upon the other person! I ran into this quote from Proust on the web that sums it up neatly. I think it's from Swann's Way:

"He made what apology he could and hurried home, overjoyed that...he had not now, by a demonstration of jealousy, given her that proof of the excess of his own passion which, in a pair of lovers, fully and finally dispenses the recipient from the obligation to love the other enough."

And from Stendhal:

"If one is sure of a woman's love, one looks to see whether she is beautiful or not; if one is doubtful of her heart there is no time to inspect her face."