A genuine work of art must mean many things; the truer its art, the more things it will mean. If my drawing, on the other hand, is so far from being a work of art that it needs THIS IS A HORSE written under it, what can it matter that neither you nor your child should know what it means? It is there not so much to convey a meaning as to wake a meaning. If it do not even wake an interest, throw it aside. A meaning may be there, but it is not for you. If, again, you do not know a horse when you see it, the name written under it will not serve you much.