Page:Reflections on the Motive Power of Heat.djvu/231

Rh have been thoroughly tested. Nothing to do with others.”

“Question thyself to learn what will please others.”

“No useless discourse. All conversation which does not serve to enlighten ourselves or others, to interest the heart or amuse the mind, is hurtful.”

“Speak little of what you know, and not at all of what you do not know.”

“Why not say more frequently, ‘I do not know’?”

“Speak to every one of that which he knows best. This will put him at his ease, and be profitable to you.” “Abstain from all pleasantry which could wound.”

“Employ only expressions of the most perfect propriety.”

“Listen attentively to your interlocutor, and so prepare him to listen in the same way to your reply, and predispose him in favor of your arguments.”

“Show neither passion nor weariness in discussion.”

“Never direct an argument against any one. If you know some particulars against your adversary, you have a right to make him aware of it to keep