For me, compatibility is a sense of humour, being able to laugh together; that is very important.
I know not if the dark or bright shall be by lot; if that wherein my hopes delight be best or not.
On two occasions I have been asked, 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.