... are concepts ...

In their essence, human values are cognitive representations of human motives. They are not direct perceptions of needs nor are they other feelings. Values are conceptions, by reason reshaped ideas of what is good and desired for an individual.

... desired ...

Values are unconditionally desired to everyone. Their importance can be judged only relatively - in relation to other values. No higher measure (“supervalue”) exists which could be used to judge the importance of human values.

... of basic categories ...

There are not many values, because they are the broadest motivational categories. There are as many personal values as there are basic human motives (biological and social).