It's Night and Day

After reading this quote, I found it possible to apply many meanings to it. However, since this is the case for most quotes I assume that should narrow it down to the most seemingly relevant. My first interpretation is that if one is true and accepts himself and his surroundings, the people around him will not doubt that he is so. Basically, it says that if someone is comfortable, in the most abstract terms, then it shows. An example of this is very easy to find. Look around you and, provided there are people nearby, you will see various types of people. Some will be very loud, some will be closely knit groups, some will all have mow hawks, and some will simply be relaxed and most likely smiling. All of these types can overlap, obviously, but the relaxed ones will stand out. These people are the living examples of the quote. Other people can sense this and they are known for being this way.
My second interpretation is very similar to my first, but deserves its own explanation none the less. If someone does not fool himself into believing something and simply confronts the world for what it is, then other people will not take him for being fake or a liar and he can be trusted. Someone that purposefully does not see the real world for what it is will obviously not be able to communicate it to other people. In a way, this stems from my first interpretation in that these people will, in turn, be comfortable.
I think that the quote is true on most occasions. Like all things in this world, there are exceptions. After all, one can imitate being comfortable, and by imitating one is dethatching oneself from the world and moving in the opposite direction that the quote would have one believe—a good liar is always good at this.