(4.) Take another virtual exhibition of fear; I mean irritation and impatience of contradiction, vehemence of assertion, determination to silence others,—these are the tokens of a mind which has not yet attained the tranquil enjoyment of certitude. No one, I suppose, would say that he was certain of the Plurality of worlds: that uncertitude on the subject is just the explanation, and the only explanation satisfactory to my mind, of the strange violence of language which has before now dishonoured the philosophical controversy upon it. Those who are certain of a fact are indolent disputants; it is enough for them that they have the truth; and they have little disposition, except at the call of duty, to criticize the hallucinations of others, and much less are they angry at their positiveness or ingenuity in argument; but to call names, to impute motives, to accuse of sophistry, to be impetuous and overbearing, is the part of men who are alarmed for their own position, and fear to have it approached too nearly. And in like manner the intemperance of language and of thought, which is sometimes found in converts to a religious creed, is often attributed, not without plausibility (even though erroneously in the particular case), to some flaw in the completeness of their certitude, which interferes with the harmony and repose of their convictions. (5.) Again, this intellectual anxiety, which is incompatible with certitude, shows itself in our running back in our minds to the arguments on which we came to believe, in not letting our conclusions alone, in going over and strengthening the evidence, and, as it were, getting it by heart, as if our highest assent were only an inference. And such too is our unnecessarily declaring that we are certain, as if to reassure ourselves, and our appealing to others for their suffrage in behalf of the truths of which we are so sure; which is like our asking another whether we are weary and hungry, or have eaten and drunk to our satisfaction. All laws are general; none are invariable; I am not writing as a moralist or casuist. It must ever be recollected that these various phenomena of mind, though signs, are not infallible signs of uncertitude; they may proceed, in the particular case, from other circumstances. Such anxieties and alarms may be merely emotional and from the imagination, not intellectual; parallel to the beating of the heart, nay, as I have been told, the trembling of the limbs, of even the bravest men, before a battle, when standing still to receive the first attack of the enemy. Such too is that palpitating self-interrogation, that trouble of the mind lest it should not believe strongly enough, which, and not doubt, underlies the sensitiveness described in the well-known lines,— “With eyes too tremblingly awake, To bear with dimness for His sake.”