The Victorian era gentleman is a study in contrasts. The aristocratic men of the age deemed themselves gentlemen by virtue of their position in society. Likewise, the emerging mercantilists and industrialists also claimed the title of gentleman by virtue of their earned wealth. New England clergy, Army officers and members of Parliament were recognized as gentlemen by virtue of their trade. However, men of other trades were not given this honor. Yet the Victorian gentleman was not merely known for his position, wealth or trade alone; he was also characterized by an impeccable moral virtue, an industrious spirit and governed by a strict social code spanning back centuries to the Age of Chivalry.
In this manner, Roger Hamley is the quintessential Victorian gentleman, although he is not wealthy or powerful. When Molly is crushed at the news of her father's remarriage, Roger comforts her without giving more pain:
If Roger was not tender in words, he was in deeds. Unreasonable and possibly exaggerated as Molly’s grief had appeared to him, it was real suffering to her; and he took some pains to lighten it, in his own way, which was characteristic enough. (p. 123-124)
Compare this to John Henry Cardinal Newman's thoughts on the Victorian gentleman:
He has his eyes on all his company; he is tender towards the bashful, gentle towards the distant, and merciful towards the absurd; he can recollect to whom he is speaking; he guards against unseasonable allusions, or topics which may irritate; he is seldom prominent in conversation, and never wearisome.
He has too much good sense to be affronted at insults, he is too well employed to remember injuries, and too indolent to bear malice. He is patient, forbearing, and resigned, on philosophical principles; he submits to pain, because it is inevitable, to bereavement, because it is irreparable, and to death, because it is his destiny. If he engages in controversy of any kind, his disciplined intellect preserves him from the blunder. (from The Idea of a University, 1852)
Roger is moral to his core. He is also unfailingly industrious; he studies hard to become an eminent scientist. He is Molly's intellectual mentor, but he never patronizes her. He helps his own father accept Osborne's widow, Aimee, and his grandson, little Osborne. With great affection and even greater tactfulness, he helps his father overcome his prejudice against Aimee's Roman Catholicism and welcome little Osborne as the heir to Hamley Hall.
You might be interested to know that another Victorian character in English Literature, Arthur Conan Doyle's Sherlock Holmes, also embodies the same characteristics of the Victorian gentleman that Roger exhibits. Both use their intellect and common sense to solve moral and practical dilemmas in the lives of others.
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