There are three friendships which are advantageous, and three which are injurious. Friendship with the upright; friendship with the sincere; and friendship with the man of much observation: these are advantageous. Friendship with the man of specious airs; friendship with the insinuatingly soft; and friendship with the glib-tongued: these are injurious.
Not to converse with a man worthy of conversation is to waste the man. To converse with a man not worthy of conversation is to waste words. The wise waste neither men nor words.