In act IV, scene iii of Shakespeare's Macbeth, Macduff learns that Macbeth killed his wife and his children. Also encouraged by Malcolm, he decides not to accept the situation and say I did not do anything to cause this--which is considered as "womanly defense". Instead, he will turn his sadness into anger and decides to take revenge by killing Macbeth--which is considered as manly and honorable act. These ideal characteristics for men and women seem to be assigned by society overtime.
Earlier in the play, a "man" was considered as brave, strong, someone who does not have pity like Macbeth in act I--who fights against enemy very bravely. A "woman" on the other side is just the opposite of that: she cries, fears, and she is more passive in life; Lady Macduff is told to leave because she is in danger: "Whither should I fly? I have done no harm...why
then, alas, do I put up that womanly defence, to say I gave done no harm?"(IV,iii). Malcolm encourages Macduff to stay strong and be the "man".
Macbeth was encouraged to do similar things in act III, scene IV: "What man dare, I dare: Approach thou like the rugged Russian bear...dare me to the desert with thy sword; if trembling I inhabit then, protest me the baby of a girl...", where he talks to the ghost and says that he is not scared like a little baby girl. He acts brave like Macduff, who decides to kill Macbeth. "Man" does not fear anything too. Macbeth, being one of the bravest men in his society answers the question of Lady Macbeth, "...are you a man?" in a fearless way: "Ay, and a bold one, one dare to look on that which might appal the devil"(III,iv) and...