But here arises a doubtful question, which is not to be passed over without being put and answered.  Some calumniator of the Truth might be able to say that if, by increasing desire in their acquisition, riches are imperfect and therefore vile, for this reason science or knowledge is imperfect and vile, in the acquisition of which the desire steadily increases, wherefore Seneca says, “If I should have one foot in the grave, I should still wish to learn.”

But it is not true that knowledge is vile through imperfection.  By distinction of the consequences, increase of desire is not in knowledge the cause of vileness.  That it is perfect is evident, for the Philosopher, in the sixth book of the Ethics, says that science or knowledge is the perfect reason of certain things.  To this question one has to reply briefly; but in the first place it is to be seen whether in the acquisition of Knowledge the desire for it is enlarged in the way suggested by the question, and whether the argument be rational.  Wherefore I say that not only in the acquisition of knowledge and riches, but in each and every acquisition, human desire expands, although in different ways; and the reason is this:  that the supreme desire of each thing bestowed by Nature in the first place is to return to its first source.  And since God is the First Cause of our Souls, and the Maker of them after His Own Image, as it is written, “Let us make Man in Our Image, after Our likeness,” the Soul especially desires to return to that First Cause.  As a pilgrim, who goes along a path where he never journeyed before, may believe every house that he sees in the distance to be his inn, and, not finding it to be so, may direct his belief to the next, and so travel on from house to house until he reach the inn, even so our Soul, as soon as it enters the untrodden path of this life, directs its eyes to its supreme good, the sum of its day’s travel to good; and therefore whatever thing it sees which seems to have in itself some goodness, it thinks to be the supreme good.  And because its knowledge at first is imperfect, owing to want of experience and want of instruction, good things that are but little appear great to it; and therefore in the first place it begins to desire those.  So we see little children desire above all things an apple; and then, growing older, they desire a little bird; and then, being older, desire a beautiful garment; and then a horse, and then a wife, and then moderate wealth, and then greater wealth, and then still more.  And this happens because in none of these things that is found for which search is made, and as we live on we seek further.  Wherefore it is possible to see that one desirable thing stands under the other in the eyes of our Soul in a way almost pyramidal, for the least first covers the whole, and is as it were the point of the desirable good, which is God, at the basis of all; so that the farther it proceeds from the point towards the basis, so much the greater do the desirable good things appear; and this is the reason why, by acquisition, human desires become broader the one after the other.