why did I think Don would go on forever? because he did not let an obstacle stand in his way. because he had outrun death already. because there was another groundbreaking study that needed to get done. because there was another know-it-all on a soapbox who could use some extra schooling. because he could teach them humility without humiliating them. because he was a giant at a time when too few giants roam. because he was a mensch, a mentor and a friend. because we who walk in his path might someday inspire another to walk in ours, and on and on.  

— Mark Arax

What are your memories of Don?
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