Friendship, according to the philosophers, is founded on resemblance. The more two persons have in common, the easier for them to be friends.

‘Pares cum paribus facillime congregantur.’ In the absence of books and a reliable memory I venture to think that this is Cicero expounding the foundation of friendship with Laelius for mouthpiece.

St. Thomas I am happily able to quote. He is emphatic and explicit.

‘Is likeness a cause of love? It seems not. Potters, says Aristotle, quarrel with one another. A man, says Augustine, loves in another what he would not be himself : he loves an actor, but would not himself be one. Sick men love health and poor men riches. We all love those who give us money and health; and those who continue friends of their dead. So likeness cannot, it seems, be a cause of love.

‘On the other hand, however, it is written in Eccle-siasticus : Every beast loveth his like.

’ My own answer is that likeness, properly speaking, is a cause of love. But there are two kinds of likeness. Actual presence of the same quality in two things make them alike. Thus two white things are alike. But presence and absence of the same quality in two things can also make them alike, when the thing that lacks the quality tends to it. Thus a body at rest and a body in motion are alike in respect of rest and motion, which are the same fundamentally, since related as act to potency.

‘The first kind of likeness begets the love of friendship ; the second, the love of concupiscence, or friendship based on usefulness or pleasure.