Most of us scriveners feel obliged to call our books something catchy in the hope of impressing potential readers with how clever we are. Not so Joseph Epstein. “What’s your book about?” “Gossip.” “What’s it called?” “Gossip.” Epstein has repeatedly opted for titles with the generic ring of labels on the files he must have kept for his research: “Ambition,” “Friendship,” “Snobbery,” “Envy.” On the part of any other writer, this might be taken as a sign of laziness or exhaustion. But in Epstein’s case, it seems a bold grab to own a great big subject, even — or especially — one on which the Almighty has had a tendency to dominate the conversation.