This is a very basic form of validity in which you determine if a measure appears (on the face of it) to measure what it is supposed to measure. In other words, does the measure "appear" to measure what it is supposed to measure? For example, if you were going to measure anxiety, does your measure appear to actually measure anxiety? If so, it has face validity. Obviously this is not a test you should use to determine if a measure should be used, but more of a first step in determining validity.