Some detractors of design will say that the design hypothesis is in fact implausible and just as implausible as physical necessity or chance. For example, it is sometimes said that on the design hypothesis, the existence of the designer himself remains unexplained. It’s said that an intelligent mind also exhibits complex order so if the universe needs an explanation, then the designer also needs an explanation. And if you say “well the designer has no explanation” then why not say the same thing about the universe, that it has no explanation for the observed fine-tuning?
This objection I think however is based upon a misconception of the nature of explanation. It’s widely recognized in the philosophy of science that in order to recognize an explanation as the best, you don’t need to have an explanation of the explanation. Indeed positing such a requirement would lead immediately to an infinite regress of explanation so that everything would become inexplicable and science would be destroyed.
So for example if archaeologists were digging in the earth and they came across things looking like tomahawk heads and pottery shards, they would be justified in inferring that these are not the chance products of metamorphosis and sedimentation but that these are artifacts of intelligent agents, even if they had absolutely no idea who these agents were or how they came to be there.
In order to recognize an explanation as the best, you don’t need to have an explanation of the explanation. And in exactly the same way, the design hypothesis being the best explanation of the fine-tuning of the universe doesn’t depend upon our being able to explain the designer. That can simply be left an open question for future inquiry.
Moreover the complexity of a mind behind the universe is not really analogous to the complexity of the universe. Certainly a mind’s ideas may be complex but a mind itself is a remarkably simple entity, being an immaterial entity which is not composed of parts or or pieces. Moreover properties like intelligence, consciousness and volition are not contingent properties which our mind could lack. Rather they’re essential to the nature of mind so that they must be possessed by a mind.
So postulating an uncreated mind behind the cosmos is not at all like postulating an undesigned cosmos with all of its contingent and variegated constants and quantities mysteriously fine-tuned for life so that I think that the hypothesis of a designer behind the universe most simply, most certainly does represent an advance in simplicity. It is a much simpler hypothesis in terms of the entity postulated than the contingent and variegated universe. And therefore it seems to me that the design hypothesis is superior to the hypotheses of physical necessity or chance and therefore is the best explanation of the fine-tuning of the universe.