I will now shew how That matter stands with relation to Connoissance in its several Branches, The Knowledge of the Goodness of a Picture, Drawing, &c. The Distinguishing of Hands, and Originals, and Copies.
Rules may be establish’d so clearly derived from Reason as to be Incontestable. If the Design of the Picture be (as in General it is) to Please, and Improve the Mind (as in Poetry) the Story must have all possible Advantages given to it, and the Actors must have the Utmost Grace, and Dignity their several Characters will admit of : If Historical, and Natural Truth only be intended That must be follow’d ; tho’ the Best Choice of These must be made ; In Both Cases Unity of Time, Place, and Action ought to be observ’d : The Composition must be such as to make the Thoughts appear at first Sight, and the Principal of them the most conspicuously ; And the Whole must be so contrived as to be a Grateful Object to the Eye, both as to the Colours, and the Masses of Light, and Shadow. These things are so evident as not to admit of any Dispute, or Contradiction ; As it also is that the Expression must be Strong, the Drawing Just, the Colouring Clean, and Beautiful, the Handling Easy, and Light, and all These Proper to the Subject. Nor will it be difficult to know Assuredly what is so, unless with relation to the Justness of the Drawing ; but to know in the Main whether any thing is Lame, Distorded, Mis-shapen, ill Proportioned, or Flat, or on the contrary Round, and Beautiful is what any Eye that is tolerably Curious can judge of.