With what care the subject is to be approached

Although the hasty execution and controversial tone of the former portions of this essay have been subjects of frequent regret to the writer, yet the one was in some measure excusable in a work referred to a temporary end, and the other unavoidable in one directed against particular opinions. Nor is either of any necessary detriment to its availableness as a foundation for more careful and extended survey, in so far as its province was confined to the assertion of obvious and visible facts, the verification of which could in no degree be dependent either on the care with which they might be classed, or the temper in which they were regarded. Not so with respect to the investigation now before us, which, being not of things outward, and sensibly demonstrable, but of the value and meaning of mental impressions, must be entered upon with a modesty and cautiousness proportioned to the difficulty of determining the likeness, or community, of such impressions, as they are received by different men; and with seriousness proportioned to the importance of rightly regarding those faculties over which we have moral power, and therefore in relation to which we assuredly incur a moral responsibility.