One of the variants of moral apologetics is epistemic. Angus Ritchie’s From Morality to Metaphysics is one example; Mark Linville’s excellent work is another. Another is R. Scott Smith’s excellent recent book called In Search of Moral Knowledge. Here is an interview of him conducted by Joe Gorra and the Evangelical Philosophical Society.
Photo: "Searching for Seashells" by C. Ford. CC license.