1. For instance: boys at school look like each other, and pursue the same studies, some of them with greater success than others; but it will sometimes happen, that those who acquitted themselves but poorly in class, when they come into the action of life, and engage in some particular work, which they have already been learning in its theory and with little promise of proficiency, are suddenly found to have what is called an eye for that work—an eye for trade matters, or for engineering, or a special taste for literature—which no one expected from them at school, while they were engaged on notions. Minds of this stamp not only know the received rules of their profession, but enter into them, and even anticipate them, or dispense with them, or substitute other rules instead. And when new questions are opened, and arguments are drawn up on one side and the other in long array, they with a natural ease and promptness form their views and give their decision, as if they had no need to reason, from their clear apprehension of the lie and issue of the whole matter in dispute, as if it were drawn out in a map before them. These are the reformers, systematizers, inventors, in various departments of thought, speculative and practical; in education, in administration, in social and political matters, in science. Such men indeed are far from infallible; however great their powers, they sometimes fall into great errors, in their own special department, while second-rate men who go by rule come to sound and safe conclusions. Images need not be true; but I am illustrating what vividness of apprehension is, and what is the strength of belief consequent upon it. 2. Again:—twenty years ago, the Duke of Wellington wrote his celebrated letter on the subject of the national defences. His authority gave it an immediate circulation among all classes of the community; none questioned what he said, nor as if taking his words on faith merely, but as intellectually recognizing their truth; yet few could be said to see or feel that truth. His letter lay, so to say, upon the pure intellect of the national mind, and nothing for a time came of it. But eleven years afterwards, after his death, the anger of the French colonels with us, after the attempt upon Louis Napoleon’s life, transferred its facts to the charge of the imagination. Then forthwith the national assent became in various ways an operative principle, especially in its promotion of the volunteer movement. The Duke, having a special eye for military matters, had realized the state of things from the first; but it took a course of years to impress upon the public mind an assent to his warning deeper and more energetic than the reception it is accustomed to give to a clever article in a newspaper or a review.