Take the following as truth: Influenced by the psychoanalyst Bruno Bettelheim's research showing that the Nazi concentration camps infantilized their inmates, Elkins argued that the closed system of slavery was so cruel and all-encompassing that none but the most stouthearted could survive without their wills being broken or their psyches damaged.
Then the following statement: "Bettelheim researched Nazi concentration camps for thirty years." is true, false, or inconclusive?