“The ability to foresee that some things cannot be foreseen is a very necessary quality.” The French philosopher Jean Jacques Rousseau probably didn’t know how relevant to investing his words were. But over 250 years after he wrote them, a client reminded us of Mr. Rousseau’s genius when that client sent us this, back in August: This is a Goldman Sachs forecast, issued in early August. Our client was very nervous that Goldman Sachs believed the stock market would be down 8.8% over the next three months. Fast forward… The sun is shining, our client is happy, and, despite the …