Ernest.—The palate of these animals must surely be made of iron, to be able to chew such a thorny substance without injury.
Fritz.—Why so? Camels and asses are very fond of thistles, and appear to digest them extremely well. It is probable, therefore, that the stomach of these animals is so formed, that these prickly substances occasion in it only an agreeable excitation, favourable to their appetite and their digestion.
Father.—Your idea is not a bad one; and if it be not true, it is at least probable.
Fritz.—Will you tell me, father, the precise difference between true and probable?
Father.—Your question is one of those which have occupied the attention of philosophers for two thousand years. It would therefore be too tedious to discuss at this moment; I will, however, endeavour to make my answer such, as to be of use to you, in the science of logic, or the art of reasoning. Let us see, if you will understand it. What we call true, is that which cannot in any way be contradicted, and which exactly agrees, in every point, with the idea we conceive of a certain object, or as it really exists before our eyes: for example, when I make an impression with my seal on some warm wax, it is absolutely true that the figure impressed on the wax, is the same as that on the seal. A thing is probable, when we have a variety of motives for believing it true, without, however, being able to bring any proof. Again, we call false, that which is in positive contradiction to all our notions, our reason, and our experience. Is it true, probable, or false, that a man can fly up into the air?
All.—It is false, absolutely false.
Father.—How so?
Jack.—Because the thing is impossible.
Father.—Very well, my young philosopher, and why is the thing impossible?
Jack.—Because it is not possible.