What the essence is and in what sense it is independent, has been stated universally in a way which is true of every case, and also why the formula of the essence of some things contains the parts of the thing defined, while that of others does not; and we have stated that in the formula of the substance the material parts will not be present (for they are not even parts of the substance in that sense, but of the concrete substance; but of this there is in a sense a formula, and in a sense there is not; for there is no formula of it with its matter, for this is indefinite, but there is a formula of it with reference to its primary substance eg in the case of man the formula of the soul for the substance is the indwelling form, from which along with the matter the so called concrete substance is derived; eg concavity is a form of this sort, for from this and the nose arise snub nose and snubness; 'nose' will be found to be involved twice in these terms ); but in the concrete substance, eg a snub nose or Callias, the matter also will be present.