“On which the sketch, as it may be called, of the picture is to be disposed,” &c. It is not without reason, nor by chance, that our author uses the word _machina_. A machine is a just assembling or combination of many pieces, to produce one and the same effect. And the disposition in a picture is nothing else but an assembling of many parts, of which we are to foresee the agreement with each other, and the justness to produce a beautiful effect, as you shall see in the 4th precept, which is concerning the economy. This is also called the composition, by which is meant the distribution and orderly placing of things, both in general, and in particular. [*†75.] “Which is what we properly call invention,” &c. Our author establishes three parts of painting; the _invention_; the _design_, or _drawing_; and the _colouring_, which in some places he also calls the _cromatic_. Many authors who have written of painting, multiply the parts according to their pleasure; and without giving you, or myself, the trouble of discussing this matter, I will only tell you, that all the parts of painting which others have named, are reducible into these three which are mentioned by our author. For which reason, I esteem this division to be the justest: and as these three parts are essential to painting, so no man can be truly called a painter, who does not possess them all together: in the same manner that we cannot give the name of man to any creature which is not composed of body, soul, and reason, which are the three parts necessarily constituent of a man. How therefore can they pretend to the quality of painters, who can only copy and purloin the works of others, who therein employ their whole industry, and with that only talent would pass for able painters? And, do not tell me, that many great artists have done this; for I can easily answer you, that it had been their better course to have abstained from so doing; that they have not thereby done themselves much honour, and that copying was not the best part of their reputation. Let us then conclude, that all painters ought to acquire this part of excellence; not to do it, is to want courage, and not dare to shew themselves. It is to creep and grovel on the ground; it is to deserve this just reproach, _O imitatores, servum pecus!_ It is with painters, in reference to their productions, as it is with orators: a good beginning is always costly to both; much sweat and labour is required, but it is better to expose our works, and leave them liable to censure for fifteen years, than to blush for them at the end of fifty. On this account, it is necessary for a painter to begin early to do somewhat of his own, and to accustom himself to it by continual exercise; for so long as, endeavouring to raise himself, he fears falling, he shall be always on the ground. See the following observation. [*†76.]