I’m not a philosopher. So I’m just poking around here, not trying to claim too much. But it seems to me that one of the best lines of apologetic argument is to argue from the premise of some good of human existence or human flourishing, on to a demonstration that this “good” only makes sense in light of the existence of God.
This is nothing new, but it seems to me potent. Putting together a number of these arguments helps demonstrate that Christianity is the most livable worldview; that it not only makes the best sense of the world logically, but that it makes the most sense of, and is the most consistent in terms of, lived human experience.
C. S. Lewis makes a number of these arguments in Mere Christianity, arguing from the existence of morality or a moral law in the beginning of that book, on to the existence of a Lawgiver; or arguing from the existence of a deep universal, unfulfilled desire, on to the reality of God, as in his chapter on Hope.
So it seems you could put together arguments for God based on things like “gratitude”; something like this:
- It is good for humans to live grateful lives. (or, Gratitude is essential to human flourishing.)
- Ultimately gratitude makes no sense apart from a transcendant good and an ultimate Giver.
- Therefore, there is an ultimate Giver – God.
Philosophers would formulate this better, and they probably have. Chesterton argued this in a number of ways. But it seems to me very fruitful ground for reflection, and for Christian apologetic living. Living a life of gratitude is beautiful and good, and yet that life makes the most sense only in the context of the existence of God. As Chesterton said somewhere, the athiest’s loneliest moment is when something happens that fills him with immense gratitude, and he realizes he has no one to thank.