Many critics of Christian belief in any sense of special or intentional creation often object that if man is God’s creation, and supposed to be the crown of his creation, as representing the perfect creature, then God is not an intelligent Demiurge (Architect). People will complain that the human body has many defects ‘by design’ which could surely have been avoided by a more careful creator. In other words, the human body has not been given an apt disposition, and the conclusion is either that it was not created by God, or at least that God was indifferent to the disposition of the body. Such points are thought to be stellar arguments in the eyes of those who employ them. I would like to offer here Aquinas’ response to such arguments, as it may be the most succinct and sharp treatment of the issue. I invite everyone to read the entire Third Article, but I will only post Aquinas’ position outlined before his rebuttals.
I answer that, All natural things were produced by the Divine art, and so may be called God’s works of art. Now every artist intends to give to his work the best disposition; not absolutely the best, but the best as regards the proposed end; and even if this entails some defect, the artist cares not: thus, for instance, when man makes himself a saw for the purpose of cutting, he makes it of iron, which is suitable for the object in view; and he does not prefer to make it of glass, though this be a more beautiful material, because this very beauty would be an obstacle to the end he has in view. Therefore God gave to each naturalbeing the best disposition; not absolutely so, but in the view of its proper end. This is what the Philosopher says (Phys. ii, 7): “And because it is better so, not absolutely, but for each one’s substance.”
Now the proximate end of the human body is the rational soul and its operations; since matter is for the sake of the form, and instruments are for the action of the agent. I say, therefore, that God fashioned the human body in that disposition which was best, as most suited to such a form and to such operations. If defect exists in the disposition of the human body, it is well to observe that such defect arises as a necessary result of the matter, from the conditions required in the body, in order to make it suitably proportioned to the soul and its operations.
~St. Thomas Aquinas, Summa Theologica, Prima Pars, Question 91, Article 3
Therefore, an apologetic along these lines would look to the end of the human body as orienting man towards God, and this might clearly be done more perfectly if the body has defects than if it gives the subject whose body it is the impression of being self-sufficient. For, as the Scriptures say;
This is what the LORD says:
Cursed is the one who trusts in man, who depends on flesh for his strength and whose heart turns away from the LORD.
Thus it is in recognition of one’s frailty and inadequacy that one may search for that which is truly adequate and strong, which is simply God.
Alternatively perhaps something could be said, as is argued in that section of the Summa, about the appropriateness of the body being not itself an ‘ex nihilo’ creation, but being formed from that which already was part of creation. This may make it appropriate, even if not inevitable, that man has some of the peculiar defects man has insofar as the disposition of the body is concerned.