In INTELLIGENT DESIGN THEORY AND THE SUPERNATURAL — THE “GOD OR EXTRA-TERRESTRIALS” REPLY philosopher Elliot Sober lays out an argument that he says "is not an argument that I am advocating, but one to which ID theorists need to respond":
Sober's argument:
If a system found in nature is irreducibly complex, then it was caused to exist by an intelligent designer.
Some of the minds found in nature are irreducibly complex.
Therefore some of the minds found in nature were caused to exist by an intelligent designer.
Any mind in nature that designs and builds an irreducibly complex system is itself irreducibly complex.
If the universe is finitely old and if cause precedes effect, then at least one of the minds found in nature was not created by any mind found in nature.
The universe is finitely old.
Causes precede their effects.
Therefore, there exists a supernatural intelligent designer.
Now, there are points of this argument that could be open for discussion. For example, does Sober adequately support premise (2), that some minds are irreducibly complex? But the argument is, on the whole, logically valid.
However, DaveScot of Uncommon Descent doesn't agree. In his 'deconstruction' of Sober, DS tries to show that the conclusion of Sober's argument is wrong (since ID cannot be seen to support theism). But where DS sees flaws in Sober's argument, I see poor reasoning by DS.
Here are his replies to Sober's points:
2. Some of the minds found in nature are irreducibly complex.
We only have one mind to examine in nature and we don’t know what causes it to exist. Therefore we cannot say that it is irreducibly complex. Given 2 is a false premise and is Sober’s first flaw.
Right away DS is off track. The definition of 'irreducible complexity' does not depend on causation. Sober provides Behe's definition: "...a single system composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively stop functioning." There is no mention of what caused the supposedly irreducibly complex system. In fact, the entire point of Behe's argument is that irreducible complexity entails that the system could not be caused by incremental process such as evolution. If we need to know the cause of some thing in order to call it irreducibly complex, Behe's argument would be vacuous.
It could be that this premise is problematic, since the notions of 'mind' and 'irreducible complexity' are not terribly precise. Sober does try to give some justification for the premise, something that DS seems to ignore altogether. DS needs to do more work to dismiss this premise.
3. Therefore some of the minds found in nature were caused to exist by an intelligent designer.
This conclusion is unsupported due to the false premise in given 2. Even if it were not fallacious it does not assert that all minds found in nature are of intelligent cause. This is Sober’s second flaw. He fails to demonstrate that all minds in nature depend on intelligent causation.
A minor quibble: the argument Sober gave in 1,2, and 3 is valid. If one of the premises is false, then the argument is not sound, not fallacious. But it's not that significant.
What is more significant is the irrelevancy of DS's complaint that Sober "fails to demonstrate that all minds in nature depend on intelligent causation." That's not what Sober is trying to do -- his argument concludes only that some minds are caused by an intelligent designer. DS is criticizing Sober for not proving something that Sober wasn't trying to prove.
4. Any mind in nature that designs and builds an irreducibly complex system is itself irreducibly complex.
We have no idea how many minds exist in nature much less whether they are all necessarily irreducibly complex. Another false premise given by Sober and his third flaw.
DS misstates the premise. Sober is not saying that all minds in nature exhibit irreducible complexity. He is saying that if a mind has designed and built an irreducibly complex system then the mind itself must be irreducibly complex. It could very well be that there are no minds in nature (though I don't think that most people would want to adopt that premise without some justification); Sober's premise is silent on that point.
This premise is crucial: it is a key part of the "who designed the designer?" argument that DS dismisses as an infinite loop. Unfortunately he fails to see that the argument requires an answer, one that Sober is asking for. Is it possible for an intelligent agent (that causes an irreducibly complex system to exist) to not itself contain some irreducibly complex components?
5. If the universe is finitely old and if cause precedes effect, then at least one of the minds found in nature was not created by any mind found in nature.
It does not follow from finite age and cause/effect that there must exist a mind in nature that was not created by another mind. We do not know how minds are created, even our own, to say nothing of minds never observed. Flaw number four.
DS is basically giving an argument from ignorance: Since we don't know how minds are created, we can't say anything about the chain of causation linking irreducibly complex minds. However, Sober gives a more detailed argument to support this premise, one that DS seems to ignore.
In particular, Sober posits that the time for an intelligent designer to create a new mind in nature is finite but positive; with this and a finite age of the universe, there can only be finitely many intelligent designers (the number may be huge, but still finite). Perhaps Sober is wrong, but DS needs to explain why Sober's assumption is not justified, other than simply saying "we don't know".
6. The universe is finitely old.
No one knows if the universe is finitely old as physics has no means of describing what came before a singularity known as the big bang nor does physics have a means of describing what if anything existed outside the singularity. This is why we speak of an “observable” universe. The observable universe appears to have a finite age but there is no way of knowing what, if anything, is beyond the bounds of the observable. Sober lacks a basic understanding of the limits of physics in describing the universe. This is flaw number five.
Sober provides a footnote that gives an age of the universe suggested by the 'big bang' cosmological theory. While it is true that there are areas open for questions related to specific inflationary models, there is significant evidence for the general theory. Sober is well within standard scientific understanding to refer to a 'start' of the universe. DS is again using an argument from ignorance: we don't know if the universe is finitely old so Sober's premise must be false.
7. Causes precede their effects.
This is also something physics does not unambiguously demonstrate. It is not demonstrated by any means that the observable universe is deterministic. There is a wide belief among quantum physicists that quantum uncertainty is real and not just an artifact of incomplete knowledge. If quantum uncertainty is real and quantum events influence macroscopic events then effects can exist without cause. This is Sober’s sixth flaw.
Sober provides a weakened form of this premise that DS does not address: "cause must precede effect when the cause is an intelligenct designer's designing and constructing an irreducibly complex system and the effect is that system's existing and being irreducibly complex" (Footnote 7). In this form, Sober is referring to a speific kind of 'cause' and 'effect' where it is not as clear that quantum mechanics necessarily plays a part.
But DS misses Sober's point anyway. Sober is not claiming that effects can exist without cause. Sober is saying that if an effect has a cause then that cause comes first. Again, QM may play a part, but for DS to use this as a refutation of Sober's premise, he needs to establish that the kinds of causes and effects Sober is concerned with are subject to QM, not just that they could be.
8. Therefore, there exists a supernatural intelligent designer.
As I have shown this conclusion is based on so many logical and scientific fallacies it is laughable. About the only thing that Sober got right was in the first assertion that irreducibly complex systems must be intelligently designed. And that itself is hotly debated too but we ID theorists accept it as a given.
DS's point is logically flawed---he has committed a 'bad reasons' fallacy: the argument for a conclusion is flawed therefore the conclusion must be false. But the conclusion may still be true, even if Sober's argument has failed to convince DS, or if DS simply doesn't want to accept the conclusion because he needs to deny that ID implies the existence of a supernatural designer.
As I mentioned, Sober's argument is open to criticism. (See this post at Panda's Thumb by Pim van Meurs for more discussion of the article and the ID response to it.) Unfortunately, DaveScot doesn't provide any real discussion of the points, but instead misrepresents Sober's argument, appeals to arguments from ignorance, and, ultimately, rejects the conclusion because he thinks the argument is invalid, a logically invalid conclusion itself.