The four loves C.S. Lewis distinguishes here are Affection, Friendship, Eros and Charity. He sees how each merges into another, how one can even become another, without losing sight of the necessary and real differentiation between them. He knows the peculiar values of each without supposing any to be all in all or self sufficient; and he discerns too the deceptions and distortions which can render the first three the natural loves dangerous without the sweetening grace of Charity the divine love which must be the sum and goal o all.