If God (as defined by classic theism) does not exist, where do qualities such as beauty, goodness or even truth come from? These qualitative aspects are dependent upon some subjective “being” or other to impose them, no? It would seem that the onus is on those, perhaps you, who hold that truly objective grounds for morality can exist without God.
It would seem that such qualitative aspects as beauty or goodness can only be an actual aspect of reality if reality itself derives from an absolute Subject superior to reality that instills those qualities into it. Qualitative aspects would, only then, precede the objective brute facts because the Subjective bringer of these qualities has precedence over lifeless reality.
I would say that you are correct in what you say, generally. Truth, goodness, beauty, morality require a " ground " in the existence of God who is the real existing, living being in whom truth, goodness, beauty are identified with his existence and who therefore is the cause of truth, goodness, beauty in the natures he brought into existence. I would say that these are not, however, " qualities, " as you suggest but realities existing in the natures which have been created. Morality is a special reality since it has to do only with the intelligent beings which have been created. Beings which are indeed living " subjects.".
God, the author of all created being directs all beings to their proper ends as envisioned by the Divine Intellect. Non intelligent, non living beings are directed by the law of their nature created with the creation of their natures.
Leaving aside the angelic nature as a special subject, I will address living human nature, Man. God directs man by a law created along with his created nature. But that law is written into a soul having an intellect and free will which is designed to lead the human person to his proper end through the proper application of the intellect and free will to the realities the person’s existence. In other words, the person’s intellect and free will are designed to perceive the true, the good, and the beautiful and to act in a way which will lead him to his proper end. So the law of morality is the proper application of the intellect and free will so as to direct the person to his proper end.
Man is able to discern the proper behaviors which will lead him to his proper end because his nature is of such a form that it can recognize what is proper and what is not. This does require the proper exercise of the intellect and will however. But the intellect was designed to recognize this. This leaves aside the necessity of a Divine Revelation.
So without God and without a living, intelligent subject, there would be no possibility of an objective morality. If God did not exist, there would be no morally good or bad behavior. Behavior would subject to the dictates of some tyrannical power. Linus