"There is a natural tendency in sects to narrow the mind. The extreme stress laid upon differences of minor importance, to the neglect of more general truths and broader views of things, gives an inverted bias to the understanding; and this bias is continually increased by the eagerness of controversy, and captious hostility to the prevailing system. A party-feeling of this kind once formed will insensibly communicate itself to other topics; and will be too apt to lead its votaries to a contempt for the opinions of others, a jealousy of every difference of sentiment, and a disposition to arrogate all sound principle as well as understanding to themselves, and those who think with them. We can readily conceive how such persons, from fixing too high a value on the practical pledge which they have given of the independence and sincerity of their opinions, come at last to entertain a suspicion of every one else as acting under the shackles of prejudice or the mask of hypocrisy. All those who have not given in their unqualified protest against received doctrines and established authority, are supposed to labour under an acknowledged incapacity to form a rational determination on any subject whatever. Any argument, not having the presumption of singularity in its favour, is immediately set aside as nugatory. There is, however, no prejudice so strong as that which arises from a fancied exemption from all prejudice. For this last implies not only the practical conviction that it is right, but the theoretical assumption that it cannot be wrong. From considering all objections as in this manner "null and void,” the mind becomes so thoroughly satisfied with its own conclusions, as to render any farther examination of them superfluous, and confounds its exclusive pretensions to reason with the absolute possession of it."