BEWARE OF A SAD PERSON
It is not a bad thing for a person to be sad but it is a bad thing to be a sad person. The two are not the same. One is a momentary feeling, the other is an attribute. One describes an event but the other describes a person. Not all of us have a smiley face but when you see someone who is perpetually sad for reasons you cannot tie to a particular event and you still cannot find an explanation to indicate that it is just a matter of time, beware.