After thirty-five earlier chapters, we reach the point of the New Leviathan. The essence of civilization is being civil to one another (36. 5).

Henri Rousseau (French, 1844 – 1910), The Equatorial Jungle, 1909, oil on canvas, Chester Dale Collection, National Gallery of Art
That may sound trivial or tautologous. It’s not. We are talking about being civil, in the ancient sense discussed in the previous chapter:
35. 41. Behaving ‘civilly’ to a man means respecting his feelings: abstaining from shocking him, annoying him, frightening him, or (briefly) arousing in him any passion or desire which might diminish his self-respect (13. 31); that is, threaten his consciousness of freedom by making him feel that his power of choice is in danger of breaking down and the passion or desire likely to take charge (13. 67).