There are many versions of this tale originally by Hans Christian Andersen (ours, for example, is illustrated with penguins dolled up - or not - in their finery). The bottom line of this story regarldess of illustration is always the same: self-deception. It takes a young boy to finally find the bravery to point out that indeed the emperor was not wearing any clothes at all. Why do we do that, why do we hide behind the safer message, the message of the masses? Are we sheeple? Do we not have opinions? And, if our opinions are different than others, isn't that okay? In order to be individual, in order to be our unique human selves, we can't always agree. It isn't just a child who should be brave enough to point out the error(s) we see in judgement or popular opinion. How important is conformity? How important is social status? How much do we rely on the opinion of others (especially about ourselves)?
Another message in this story is the complexity of lies one must weave in order to convince others of an untruth. It is never just one lie ('The dog ate my homework'). One lie leads to another and another and another. Is the dog okay after that much paper? How much of the homework did you actually finish? Why did you not put it away? Did you learn the underlying concept? Can't you just print it out again?
Let's have the acumen, the common sense, and courage to speak the truth, the whole truth and nothing but the truth because lying doesn't make things better or easier. Lying just delays the inevitable. And, maybe most importantly, lying is just plain not nice. If someone is walking around without any clothes on, please get them a robe.