Now the conceptions whose observed incongruity with the perceptions moves us to laughter are either those of others or our own. In the first case we laugh at others, in the second we feel a surprise, often agreeable, at the least amusing. Therefore children and uneducated people laugh at the most trifling things, even at misfortunes, if they were unexpected, and thus convicted their preconceived conception of error. As a rule laughing is a pleasant condition; accordingly the apprehension of the incongruity between what is thought and what is perceived, that is, the real, gives us pleasure, and we give ourselves up gladly to the spasmodic convulsions which this apprehension excites. The reason of this is as follows. In every suddenly appearing conflict between what is perceived and what is thought, what is perceived is always unquestionably right; for it is not subject to error at all, requires no confirmation from without, but answers for itself. Its conflict with what is thought springs ultimately from the fact that the latter, with its abstract conceptions, cannot get down to the infinite multifariousness and fine shades of difference of the concrete. This victory of knowledge of perception over thought affords us pleasure. For perception is the original kind of knowledge inseparable from animal nature, in which everything that gives direct satisfaction to the will presents itself. It is the medium of the present, of enjoyment and gaiety; moreover it is attended with no exertion. With thinking the opposite is the case; it is the second power of knowledge, the exercise of which always demands some, and often considerable, exertion. Besides, it is the conceptions of thought that often oppose the gratification of our immediate desires, for, as the medium of the past, the future, and of seriousness, they are the vehicle of our fears, our repentance, and all our cares. It must therefore be diverting to us to see this strict, untiring, troublesome governess, the reason, for once convicted of insufficiency. On this account then the mien or appearance of laughter is very closely related to that of joy. On account of the want of reason, thus of general conceptions, the brute is incapable of laughter, as of speech. This is therefore a prerogative and characteristic mark of man. Yet it may be remarked in passing that his one friend the dog has an analogous characteristic action peculiar to him alone in distinction from all other brutes, the very expressive, kindly, and thoroughly honest fawning and wagging of its tail. But how favourably does this salutation given him by nature compare with the bows and simpering civilities of men. At least for the present, it is a thousand times more reliable than their assurance of inward friendship and devotion.