All this is merely saying that he, in a degree once common, but now very unusual, threw his feelings into his opinions; which truly it is difficult to understand how any one who possesses much of both, can fail to do. None but those who do not care about opinions, will confound it with intolerance. Those, who having opinions which they hold to be immensely important, and their contraries to be prodigiously hurtful, have any deep regard for the general good, will necessarily dislike, as a class and in the abstract, those who think wrong what they think right, and right what they think wrong: though they need not therefore be, nor was my father, insensible to good qualities in an opponent, nor governed in their estimation of individuals by one general presumption, instead of by the whole of their character.

What It Means

This is a placeholder explanation generated by the low-overhead model. It interprets "All this is merely saying that he, in a degree once common, but now very unusual, threw his feelings into his opinions; which truly it is difficult to understand how any one who possesses much of both, can fail to do. None but those who do not care about opinions, will confound it with intolerance. Those, who having opinions which they hold to be immensely important, and their contraries to be prodigiously hurtful, have any deep regard for the general good, will necessarily dislike, as a class and in the abstract, those who think wrong what they think right, and right what they think wrong: though they need not therefore be, nor was my father, insensible to good qualities in an opponent, nor governed in their estimation of individuals by one general presumption, instead of by the whole of their character." in the context of "(pp. 50-51)" to mean that wisdom is timeless.