How does The Merchant of Venice illustrate the theme of appearance versus reality?

To address the question of how the Merchant of Venice deals with the theme of appearance versus reality, start by reviewing the play. To be specific, look at the following things:

Look at how Antonio acts towards Shylock when talking directly to him, versus how he acts when Shylock can't hear him.

Then do the same for Shylock. What does he say privately, versus publicly?

Then, consider Portia. She dresses up like a man, changing her appearance, in order to change reality. Look at that section.

Then look at the discussions of the laws. What do they mean--and what are they interpreted to mean?

Then look at which chest is considered the right choice, versus which one different people choose. There is a conflict there between appearance and reality.

Remember this line from the play: All that glisters is not gold.