Reginald Garrigou-Lagrange offers the following as part of an argument for God’s existence:
There is, then, a purpose in our natural desire for happiness; its inclination is for some good. But is this inclination for a good that is wholly unreal, or, though real, yet unattainable?
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It will perhaps be said that our universal idea of good leads us to seek happiness in the simultaneous or successive enjoyment of all those finite goods that have an attraction for us, such as health and bodily pleasures, riches and honors, the delight in scientific knowledge, art and friendship. …
But experience and reason undeceive us. That empty void in the heart always remains, making itself felt in weariness of spirit; and intelligence tells us that not even the simultaneous possession of all these goods, finite and imperfect as they are, can constitute the good itself which is conceived and desired by us, any more than an innumerable multitude of idiots can equal a man of genius.
… Even if the whole sum of created goods were multiplied to infinity they would not constitute that pure and perfect good which the intellect conceives and the will desires. …
If therefore this natural desire for happiness cannot be ineffective, if it cannot find its satisfaction in any finite goods or in the sum total of them, we are necessarily compelled to affirm the existence of a pure and perfect good. That is, the good itself or the sovereign good, which alone is capable of responding to our aspirations. Otherwise the universal range of our will would be a psychological absurdity, something radically unintelligible and without a purpose.
Reginald Garrigou-Lagrange, O.P., Providence (1932), Part I, Section 4.