Be all Things to all Men –a discreet Proteus, learned with the learned, saintly with the sainted. It is the great art to gain every one’s suffrages; their goodwill gains general agreement. Notice men’s moods and adapt yourself to each, genial or serious as the case may be. Follow their lead,
glossing over the changes as cunningly as possible. This is an indispensable art for dependent persons. But this savoir faire calls for great cleverness. He only will find no difficulty who has a universal genius in his knowledge and universal ingenuity in his wit.

Gracian, The Art of Worldly Wisdom