O, beware, my lord, of jealousy; It is the green-ey'd monster, which doth mock The meat it feeds on.

A man should be what he seems.

As in a theatre, the eyes of men, after a well-graced actor leaves the stage, are idly bent on him that enters next.

Such antics do not amount to a man.

If I could write the beauty of your eyes And in fresh numbers number all your graces, The age to come would say, 'This poet lies; Such heavenly touches ne'er touch'd earthly faces.'

That man that hath a tongue, I say is no man, if with his tongue he cannot win a woman.

...an old man is twice a child.