A Grave Matter

He was a remarkably serious man, so serious in fact that he was sometimes described as a centre of gravity. This phrase met with his approval until a colleague expressed surprise at his equanimity towards being associated with such an exercise in playful wordplay. So stern was his perennial mental disposition, however, that the mercurial nature & levity of this phrase had entirely escaped his notice. He was deeply perturbed & fell into a depression.
It is not known whether his colleague had divined the truth & intentionally disturbed the calm, grave pool of his being with this dreadful stone of truth, but it would be unwise to dismiss such an idea.