Abraham Lincoln might have had positions that we would consider quite racist nowadays but because he became a much more moral person than his intellectual environment encouraged we rightly admire him. By contrast Campbell was somewhat retrograde to the circles he moved in as you can see from the authors he stifled. And so because he was exposed to arguments that he should have been a more decent person than he was and because far more enlightened positions were socially acceptable we are free to condemn him for his failings.