Twelfth night explores uncertainty and inconstancy in love. which set of lines in these excerpts from act ii, scene iv, shows that duke orsino considers men to be more easily swayed by passion than women? duke : too old, by heaven! let still the woman take an elder than herself; so wears she to him, so sways she level in her husband's heart. for, boy, however we do praise ourselves, our fancies are more giddy and unfirm, more longing, wavering, sooner lost and won, than women's are. … duke: there is no woman's sides can bide the beating of so strong a passion as love doth give my heart: no woman's heart so big to hold so much; they lack retention. alas, their love may be called appetite,— no motion of the liver, but the palate,— that suffer surfeit, cloyment, and revolt; but mine is all as hungry as the sea, and can digest as much: make no compare between that love a woman can bear me and that i owe olivia.

The set of lines that shows that Duke Orsino considers men to be more easily swayed by passion than women is this one: "For, boy, however we do praise ourselves, Our fancies are more giddy and unfirm, More longing, wavering, sooner lost and won, Than women's are."

The Duke, who is talking to Viola, is arguing that no matter how much men praise themselves, their "fancies" (their whims, their desires) are more "giddy" (more frivolous, more euphoric) and "unfirm" (more unsteady, since they are not firmly set), more "longing" (more craving), "wavering" (more quivering, more fluctuating), sooner lost and won (that is to say, temporal, brief, fleeting) that women's fancies. Because of this, they are more easily persuaded by passion, due to the intense, strong, enthusiastic, and uncontrollable nature of this feeling.    

when claudius uses flattery to convince laertes to kill hamlet, shakespeare emphasizes the theme “pride leads to downfall.”