I beg of you always to dwell upon the necessity of a thorough understanding of principles, in order to stop the vivacity of his mind, and please do not forget to meditate upon the subject of our discussion.
I wish to propose for the reader's favourable consideration a doctrine which may, I fear, appear wildly paradoxical and subversive. The doctrine in question is this: that it is undesirable to believe a proposition when there is no ground whatever for supposing it true.