F. And the horse ? C. The horse has small ears, ricely turned and upright. F. And the mane, is there no difference there? C. The horse has a fine long flowing mane; the ass has hardly any, F. And the tail ! is it not fuller of hair in the horse than in the ass ? C. Yes; the ass has only a few long hairs at the end of the tail; but the horse has a long bushy tail when it is not cut. F. Which, by the way, it is pity it ever should. Now, then, observe what particulars we have got. A horse is an animal of the quadruped kind, wholehoofed, with short erect ears, a flowing. mane, and a tail covered in every part with lony hairs. Now is there any other animal, think you, in the world, that answers these particulars? C. I do not know; this does not tell us a great deal about him. F. And yet it tells us enough to distinguish him from all the different tribes of the creation which we are acquainted with in any part of the earth. Do you know now what we have been making? C. What ? F. A DEFINITION. It is the business of a definition to distinguish precisely the thing defined from any other thing, and to do it in as few terms as possible. Its object is to separate the subject of definition, first, from those with which it has only a general resemblance, then, from those which agree with it in a greater variety of particulars; and so on, till by constantly throwing out all which have not the qualities we have taken notice of, we come at length to the individual or the species we wish to ascertain. It is a kind of a chase, and resembles the manner of hunting in some countries, where they first enclose a large circle with their dogs, nets, and horses; and then, by degrees, draw their toils closer and closer, driving their game before them till it is at length brought into so narrow a compass that the sportsmen have nothing to do but to knock down their prey. C. Just as we have been hunting this horse, till at last we held him fast by his ears and his tail. F. I should observe to you, that in the definition naturalists give of a horse it is generally mentioned that he has six cutting teeth in each jaw; because this circumstance of the teeth has been found a very convenient one for characterising large classes : but as it is not absolutely necessary here, I haveomitted it; a definition being the more perfect the fewer particulars you make use of, provided you can say with certainty а from those particulars the object so characterised must be this and no other whatever. C. But, papa, if I had never seen a horse, I should not know what kind of animal it was by this definition. F. Let us hear, then, how you would give me an idea of a horse. C. I would say it was a fine large prancing creature, with slender legs and an arched neck, and a sleek smooth skin, and a tail that sweeps the ground, and that he snorts and neighs very loud, and tosses his head, and runs as swift as the wind. F. I think you learned some verses upon the 'horse in your last lesson ? Repeat them. C. The wanton courser thus with reins unbound Breaks from his stall, and beats the trembling ground; Pamper'd and proud, he seeks the wonted tides, And laves, in height of blood, bis shining sides; His head, now freed, he tosses to the skies; Pope's Homer. F. You have said very well; but this is not a Definition, it is a Description. C. What is the difference ? F. A description is intended to give you a lively picture of an object, as if you saw it; it ought to be very full. A definition gives no picture to those who have not seen it: it rather tells you what its subject is not, than what it is, by giving you such clear specific marks, that it shall not be possible to confound it with any thing else ; and hence it is of the greatest use in throwing things into classes. We have a great many beautiful descriptions from ancient authors so loosely worded that we cannot certainly tell what animals are meant |