More Than the Sum of His Parts by Joe Haldeman
I’m still sorting through my feelings about this story. It’s one that takes you to the depths of madness but still flings truths at you that you’d rather not participate in. Dr. Wilson Cheetham who had three quarters of his body “thoroughly roasted” is keeping a journal of the process of having his body rebuilt. Yes, rather than let him die, they decided to rebuild him as a partial cyborg. New arm, leg, face, and genitalia.
Slowly he experiments with his new parts, but it’s the genitalia that brings him down. While testing the strength in all his parts he accidentally splits a woman in half. Disposing of her body gets complicated which drops him into a madness where he decides he wants to be a complete cyborg. This is a brutally sad story of wanting to be more than you are.
From the anthology “The Year’s Best Science Fiction” edited by Gardner Dozois 1985