in Thoreau’s Journal:

The winter, cold and bound out, as it is, is thrown to us like a bone to a famishing dog, and we are expected to get the marrow out of it…But the winter was not given to us for no purpose. We must thaw its cold with our genialness. We are tasked to find out and appropriate all the nutriment it yields.

If it is a cold and hard season, its fruit no doubt is the more concentrated and nutty. It took the cold and bleakness of November to ripen the walnut, but the human brain is the kernel which the winter itself matures.