To one thing constant never...an example of men's capriciousness as lovingly told by Shakespeare through Benedick (and through the silver screen by Kenneth Brannaugh):
I do wonder that one man, seeing how much other men are fools when they dedicate themselves to love, will, after he hath laugh’d at such shallow follies in others, become he subject of his own scorn by falling in love. And such a man is Claudio. I have known then there was no music with him but the drum and the fife of war; and now he’d rather hear the tabour and the pipe of peace. I have known when he would have walk’d ten mile a-foot to see good armour; and now will he lie ten nights awake, drawing the fashion of a new doublet. He was wont to speak plain and to the purpose, like an honest man and a soldier; and now is he turn’d poet: his words are a very fanciful banquet, just so many strange dishes. Could I be so transform’d and see with these eyes? I cannot tell; I think not. I will not be sworn, but though love may transform me into an oyster, I'll take my oath on it, that till he have made an oyster of me, he shall never make me such a fool. One woman is fair, yet I am well; another is wise, yet I am well; another virtuous, yet I am well; but till all favours be in one woman, one woman shall not earn my favour. Rich she shall be, that's certain; wise, or I'll none of her; virtuous, or I'll never speak for her; fair, or I'll never look on her; noble, or come not near me; of good conversation, an excellent musician, and her hair shall be of what colour it please God. Ha! The Prince and Monsieur Love! I will hide me in the arbour.
This can be no trick: their conference was serious. They have the truth of this from Hero. They seem to pity the lady that her affections have conquer’d her. Love me! Why, it must be requited. I hear how I am censur’d: they say I will bear myself proudly, if I perceive the love come from her; they say too that she will rather die than give any sign of affection. I did never think to marry. I must not seem proud: happy are they who hear their faults and then mend them. They say the lady is fair; 'tis a truth, I can bear them witness; and virtuous; 'tis so, I cannot deny it; and wise, but for loving me; by my troth, it is no addition to her wit, nor no great argument of her folly, for I will be horribly in love with her. I may perchance have some witty jests toss’d at me, because I have rail’d so long against marriage: but doth not the appetite alter? A man loves the meat in his youth that he cannot endure in his age. Shall witty quips frighten a man from following his fancy? No, the world must be peopled. When I said I would die a bachelor, I did not think I should live till I were married.