Self-will, love of pleasure, quick excitability, and consequent irritability, are the marked ingredients in every strong character; its strength must be employed against itself to produce any high moral superiority.
There is an analogy between the metaphysical truths above spoken of and that fact in the physical history of the world, that coal-mines are generally placed in the neighbourhood of iron-mines. This is a provision involved in the nature of the thing itself; and we know that, without the furnaces thus placed within reach, the natural capabilities of the useful ore would never be developed.
In the same way, we know that an accompanying furnace of affliction and temptation is necessarily involved in that very strength of character which we admire; and also, that, without this fiery furnace, the vast capabilities of their nature, both moral and mental, could never be fully developed.
Suffering, sorrow, and temptations are the invariable conditions of a life of progress; and suffering, sorrow, and temptations are all of them always in proportion to the energies and capabilities of the character.
There is another analogy in animated nature, illustrative of the case of those who, without injury to themselves, (the injury to our neighbour is, as I said before, a different part of the subject,) may attend the ball-room, the theatre, and the race-course. Those animals lowest in the scale of creation, those who scarcely manifest one of the energies of vitality, are also those which are the least susceptible of suffering from external causes. The medusæ are supposed to feel no pain even in being devoured, and the human zoophyte is, in like manner, comparatively out of the reach of every suffering but death. Have you not seen some beings endowed with humanity nearly as destitute of a nervous system as the medusæ, nearly as insusceptible of any sensation from the accidents of life. Some of these, too, may possess virtue and piety as well as the animal qualities of patience and sweetness of temper, which are the mere results of their physical organization. No degree of effort or discipline, however, (indeed they bear within themselves no capabilities for either,) could enable such persons to become eminently useful, eminently respected, or eminently loved. They have doubtless some work appointed them to do, and that a necessary work in God's earthly kingdom; but theirs are inferior duties, very different from those which you, and such as you, are called on to fulfil.