They are only labels and are utterly useless.

I like the cut of your jib 282RA, but you let yourself down with wild generalisations like that one. They are labels for concepts which are not yet clearly defined, and as such are immeasurably useful. If not for the labels we would not be able to discuss the concepts.

...only our mental constructs to deal with something we do not understand.

'Only'? Aren't you being a little dismissive?