b. Second Conclusion

22. A second conclusion is that in such sort of generation the form of the flesh which is introduced into the matter of the nutriment is new, because (as was argued against the preceding opinion [n.17]) the pre-existing form could not newly perfect that matter, for this possibility belongs only to a form that is altogether un-extended (as was illustrated there [n.17] about the intellective soul). For any form that is per accidens extended has a different part in different parts of the matter, and so, if new matter is perfected by the form, the new matter is not perfected by any part of the form that perfected another part of matter before.

23. An illustration of this is through the flowing away of a part generated in nutrition, because when it flows away then, just as the matter of the part ceases to be something of the whole flesh, so too does the form (which perfects the matter) cease to be part of the whole flesh, because it cannot remain or migrate without the matter.