Because in the midst of happiness there is always a seed of unhappiness; it consumes itself like fire--it can't burn forever, sooner or later it must die; and this presentiment of the end destroys my happiness when it is at is height.
August StrindbergSorrow has the fortunate peculiarity that it preys upon itself. It dies of starvation. Since it is essentially an interruption of habits, it can be replaced by new habits. Constituting, as it does, a void, it is soon filled up by a real horror vacuum.
August Strindberg