equally produce a change in the nature of the science itself. If, to take one of the simplest of examples, the mind had been formed susceptible of all the modifications which it admits at present, with the single exception of those which it receives on the presence of light, of how many objects and powers in nature, which we are now capable of distinguishing, must we have remained in absolute ignorance! But would this comparative ignorance of many objects be the only effect of such a change of the laws of mind, as I have supposed? Or rather, is it not equally certain, that this simple change alone would be sufficient to alter the very nature of the limited science of which the mind would still be capable, as much as it narrowed its extent? Science is the classification of relations; varying, too, in every case, as the relations observed are different; and how very differently should we, in such circumstances, have classed the few powers of the few objects, which might still have become known to us, since we could no longer have classed them according to any of those visual relations, which are always the most obvious and prominent. It is even, perhaps, an extravagant supposition, that a race of the blind, unless endowed with some other sense to compensate the defect of sight, could have acquired so much command of the common arts of life, or so much science of any sort, as to preserve themselves in existence. But though all this, by a very strong license of _supposition_, were taken for granted, it must surely be admitted, that the knowledge which man could in those circumstances acquire, would be not merely less in degree, but would be as truly different from that which his powers at present have reached, as if the objects of his science, or the laws which regulate them, had themselves been changed to an extent, at least as great as the supposed change in the laws of mind. The _astronomy_ of the blind, if the word might still be used to express a science so very different from the present, would, in truth, be a sort of _chemistry_. Day and night, the magnificent and harmonious revolution of season after season, would be nothing more than periodical changes of temperature in the objects around; and that great Dispenser of the seasons, the Source of light, and beauty, and almost of animation, at whose approach nature seems not merely to awake, but to rise again, as it was at first, from the darkness of its original chaos, if its separate existence could be at all inferred, would probably be classed as something similar, though inferior in power, to that unknown source of heat, which, by a perilous and almost unknown process, was fearfully piled and kindled on the household hearth.