Winter of the mind
Often one feels that one has nothing to say - that all one's thoughts are blocked somehow, iced over, inchoate and unable to find expression. A winter of the mind, an intolerable stupidity, in which nothing of intelligence can break through to the surface. And yet there might be something good in this: one can sometimes feel a concentration, a slow accumulation, of that in oneself which is most potent. "As frozen grapes make the sweetest wine..."