Even though these two plays are very different, with King Lear obviously being a tragedy and A Midsummer Night's Dream clearly falling into the category of a comedy, the two characters of Lear and Theseus do have some similarities. This can be seen in Act I scene 1 when Theseus sticks to the letter of the law and supports Egeus in the case he brings to him concerning his desire that his daughter should marry Demetrius and not Lysander. Note what he says in the following quote:
For you, fair Hermia, look you arm yourself
To fit your fancies to your father's will,
Or else the law of Athens yields you up--
Which by no means we may extenuate--
To death or to a vow of single life.
Theseus, in this scene, is presented as a harsh, unyielding figure, who confronts a girl with no hope whatsoever concerning her future. This is very similar to the character of Lear in his treatment of Cordelia at the beginning of the play, although of course Lear is much harsher with Cordelia than Theseus is with Hermia. Note what Lear says to his daughter when she refuses to wax lyrical about her love for him in the way that her sisters have done:
Here I disclaim all my paternal care,
Propinquity, and property of blood,
And as a stranger to my heart and me
Hold thee from this for ever.
Both Theseus and Lear treat Hermia and Cordelia respectively in a way that shows their male dominance and also their complete lack of understanding about the situations that these heroines are placed in. Although Theseus changes his tune by the end of A Midsummer Night's Dream, it is important to remember that both of these characters, at the beginning at least, display an attitude towards women that is rather callous and unfeeling.