Shakespeare does not really present love itself as either a positive or negative force. However, he does present the fact that love is guided by the irrational mind in a negative light. We know that he does not put a negative slant on love itself because all of the couples are happily united at the end, even Oberon and Titanius make up in the end. Also, Shakespeare gives us Theseus and Hippolyta as the one loving couple that remains strong in their relationship all throughout, showing us that love itself is not at fault, but the irrational mind.
We first see Shakespeare present the theme of the irrationality of the mind concerning love in the first scene with Helena's soliloquy. In this speech, Helena points out that all over Athens she is recognized as being as fair as Hermia, indicating that Demetrius's choice to pursue Hermia instead of Helena is irrational (I.i.232). To emphasize her point, she speaks her most important lines, "Love looks not with the eyes, but with the mind; / And therefore is wing'd Cupid painted blind" (239-240). In these lines Helena is arguing that love is an illusion; love is all in the head, rather than having anything to do with objective reality, such as beauty. These lines very clearly portray Shakespeare's theme that love is guided by irrational thought. Helena also points out that Demetrius made proclamations and vows of love to her before he saw Hermia, which is also central to the unfolding of the play as well as to the themes, as we see in her lines, "For ere Demetrius look'd on Hermia's eyne, / He hail'd down oaths that he was only mine" (247-248). By having Helena point out Demetrius's unfaithfulness to Helena, Shakespeare is pointing out how fickle love can be. Shakespeare is also telling us that had Demetrius made the more rational decision of remaining faithful to Helena, the characters would have been spared from a great deal of grief and hardship. Hence, Shakespeare created the moral ending by having Demetrius decide to remain with Helena at the end of the play, explaining that he was engaged to her before he saw Hermia and is now ready to be faithful (IV.i.173-177). Having Demetrius make the moral decision by the end of the play shows us Shakespeare's message that love can indeed be guided by rational thought, showing us that love should not be viewed negatively, but rather the irrational human mind.