By caritas, the Pope means a distinctive form of the love that
humans experience — not eros, nor amor, nor
affection, nor commitment in choice (dilectio), nor friendship, nor all those other forms of love that
humans know and
cherish, each in its own way.
Consequently, if it is not possible for him, psychologically to surround each being with that particular, overflowing
affection which characterizes our
human love, at least he can nurture in his heart that generalized but none the less real
affection for all that is which will cause him to
cherish in each thing, over and above its surface qualities, the being itself — that is to say, that indefinable, elect part of each thing which, under God's influence, gradually becomes flesh of his flesh.