Each thing that lives has its moment of self-exposition, and so has each period of each thing, if we remove the disturbing forces of accident. To do this is the business of ideal art, whether in images of childhood, youth, or age, in man or in woman. Hence a good portrait is the abstract of the personal; it is not the likeness for actual comparison, but for recollection. This explains why the likeness of a very good portrait is not always recognized; because some persons never abstract, and amongst these are especially to be numbered the near relations and friends of the subject, in consequence of the constant pressure and check exercised on their minds by the actual presence of the original. And each thing that only appears to live has also its possible position of relation to life, as nature herself testifies, who, where she cannot be, prophecies her being in the crystallized metal, or the inhaling plant. The charm, the indispensable requisite, of sculpture is unity of effect. But painting rests in a material remoter from nature, and its compass is therefore greater. Light and shade give external, as well internal, being even with all its accidents, whilst sculpture is confined to the latter. And here I may observe that the subjects chosen for works of art, whether in sculpture or painting, should be such as really are capable of being expressed and conveyed within the limits of those arts. Moreover they ought to be such as will affect the spectator by their truth, their beauty, or their sublimity, and therefore they may be addressed to the judgment, the senses, or the reason. The peculiarity of the impression which they may make, may be derived either from colour and form, or from proportion and fitness, or from the excitement of the moral feelings; or all these maybe combined. Such works as do combine these sources of effect must have the preference in dignity.