But then over these convictions there came a third,--equally strong,--which told him that the girl loved the younger man and did not love him, and that if he loved the girl it was his duty as a man to prove his love by doing what he could to make her happy. As he walked up and down the walk by the moat, with his hands clasped behind his back, stopping every now and again to sit on the terrace wall,--walking there, mile after mile, with his mind intent on the one idea,--he schooled himself to feel that that, and that only, could be his duty. What did love mean if not that? What could be the devotion which men so often affect to feel if it did not tend to self-sacrifice on behalf of the beloved one? A man would incur any danger for a woman, would subject himself to any toil,--would even die for her! But if this were done simply with the object of winning her, where was that real love of which sacrifice of self on behalf of another is the truest proof? So, by degrees, he resolved that the thing must be done. The man, though he had been bad to his friend, was not all bad. He was one who might become good in good hands. He, Roger, was too firm of purpose and too honest of heart to buoy himself up into new hopes by assurances of the man's unfitness. 
But then over these convictions there came a third, equally strong, which told him that the girl loved Montague and did not love him, and that if he loved the girl it was his duty as a man to prove his love by doing what he could to make her happy. As he walked up and down by the moat, with his hands clasped behind his back, mile after mile, he schooled himself to feel that that was his duty. What did love mean if not that? What was devotion if a man would not sacrifice himself on behalf of the beloved one?
So, by degrees, he resolved that the thing must be done. Montague was not all bad. He might become good in good hands. 