One has seen him so many times dealk with physical problems in unpredictable ingenious ways that he had come to seem immune. He had turned chronic insomnia into the opportunity to do more thinking - thinking that remained totally unperturbed by whatever troubles his frail body presented. He was a living symbol of mind over matter. One came to accept this as one accepted the help he was always ready to give.

Now he is gone and we are left to mourn a unique human being whose unceasing effort to make us understand whose generosity in matters of ideas and personal support has left us with a debt we cannot repay. He changed our way of thinking and enriched the world of ideas with more than we can hope to explore. He will not be forgotten.