"I suppose people invented calenders to smooth paper. What else could be supposed? Ah, but that is what most people would suppose, isn't it? And that nearly guarantees that said supposition is inherently wrong.
"You see, supposition is one of the greatest flaws of mankind. People supposed that the world was flat, because from their parochial and limited viewpoint, it appeared so. People supposed that the sun orbited around the earth. People supposed that the world would not be destroyed in the year 2016. Eh. . . but you shouldn't know about that yet. Sorry to ruin your day.
"But back to your question. As to calenders? Well, yes, they actually were invented to smooth out paper. That, and to confuse people, because they are spelled very much like 'calendars,' which were of course invented to make rather disappointing Christmas gifts. Or at least, that's what can be supposed. But that's a whole different issue entirely. Hmm, yes. Now would you be so kind as to pour me another cognac, please?"