Dr. Cottard was never quite certain of the tone in which he ought to reply to any observation, or whether the speaker was jesting or in earnest. And so in any event he would embellish all his facial expressions with the offer of a conditional, a provisional smile whose expectant subtlety would exonerate him from the charge of being a simpleton, if the remark addressed to him should turn out to have been facetious. But as he must also be prepared to face the alternative, he never dared to allow this smile a definite expression on his features, and you would see there a perpetually flickering uncertainty, in which you might decipher the question that he never dared to ask: “Do you really mean that?” He was no more confident of the manner in which he ought to conduct himself in the street, or indeed in life generally, than he was in a drawing-room; and he might be seen greeting passersby, carriages, and anything that occurred with a malicious smile which absolved his subsequent behaviour of all impropriety, since it proved, if it should turn out unsuited to the occasion, that he was well aware of that, and that if he had assumed a smile, the jest was a secret of his own.