though studying a breed , when you were one of the only surviving specimens of it , was a tricky situation , especially for one who could not love medical philosophy or terminology , whose memory was good but far from preternatural , whose sense of the past was often deliberately relinquished to a `` childlike '' immersion in the present , and a general fear of thinking in terms of millennia or eons or whatever people wanted to call the great spans of time which he himself had witnessed , lived through , struggled to endure , and finally cheerfully forgotten in this great enterprise suited to his few and special talents .