A student who saw my comments on intelligent design and the “god of the gaps” argument wrote me and asked this follow-up question:

If ID theory is claiming a non-materialistic explanation for “gaps” in our understanding (whether origin of the universe, irreducible complexity, etc.), i.e. a designer, would this logically imply that some things are unknowable? At least unknowable or unexplainable through scientific/materialistic research? If so, would this imply that science should stop trying to understand/research some things?

I replied by noting that the student’s question seems to assume that only materialistic answers are “knowable” whereas non-materialistic answers are “unknowable.” In fact, we can “know” that an intelligent cause is the best explanation in precisely the same way that we infer materialistic causes.

Historical sciences like Darwinian evolution and intelligent design rely on the principle of uniformitarianism, which holds that “the present is the key to the past.” Under this methodology, scientists study causes at work in the present-day world in order, as geologist Charles Lyell put it, to “explain the former changes of the Earth’s surface by reference to causes now in operation.”

Darwinian evolution applies this method this by studying causes like mutation and selection in order to recognize their causal abilities and effects in the world at present. Darwinian scientists then try to explain the historical record in terms of those causes, seeking to recognize the known effects of mutation and selection in the historical record.

Intelligent design applies this same method by studying causes like intelligence in order to recognize its causal abilities and effects in the present-day world. ID theorists are interested in understanding the information-generative powers of intelligent agents. ID theorists then try to explain the historical record by including appeals to that cause, seeking to recognize the known effects of intelligent design in the historical record.

So whether you appeal to materialistic causes like mutation and selection, or non-material causes like intelligent design, you are using the same basic uniformitarian reasoning that is well-accepted in historical sciences. Stephen Meyer explains how ID uses this kind of reasoning, providing a positive case for design:

For historical scientists, “the present is the key to the past” means that present experience-based knowledge of cause and effect relationships typically guides the assessment of the plausibility of proposed causes of past events.

Yet it is precisely for this reason that current advocates of the design hypothesis want to reconsider design as an explanation for the origin of biological form and information. This review, and much of the literature it has surveyed, suggests that four of the most prominent models for explaining the origin of biological form fail to provide adequate causal explanations for the discontinuous increases of CSI that are required to produce novel morphologies. Yet, we have repeated experience of rational and conscious agents–in particular ourselves–generating or causing increases in complex specified information, both in the form of sequence-specific lines of code and in the form of hierarchically arranged systems of parts.

In the first place, intelligent human agents–in virtue of their rationality and consciousness–have demonstrated the power to produce information in the form of linear sequence-specific arrangements of characters. Indeed, experience affirms that information of this type routinely arises from the activity of intelligent agents. A computer user who traces the information on a screen back to its source invariably comes to a mind–that of a software engineer or programmer. The information in a book or inscriptions ultimately derives from a writer or scribe–from a mental, rather than a strictly material, cause. Our experience-based knowledge of information-flow confirms that systems with large amounts of specified complexity (especially codes and languages) invariably originate from an intelligent source from a mind or personal agent. As Quastler (1964) put it, the ‘creation of new information is habitually associated with conscious activity’ (p. 16). Experience teaches this obvious truth.

… What natural selection lacks, intelligent selection–purposive or goal-directed design–provides. Rational agents can arrange both matter and symbols with distant goals in mind. In using language, the human mind routinely ‘finds’ or generates highly improbable linguistic sequences to convey an intended or preconceived idea. … Thus, by invoking design to explain the origin of new biological information, contemporary design theorists are not positing an arbitrary explanatory element unmotivated by a consideration of the evidence. Instead, they are positing an entity possessing precisely the attributes and causal powers that the phenomenon in question requires as a condition of its production and explanation.

(Stephen C. Meyer, “The origin of biological information and the higher taxonomic categories,” Proceedings of the Biological Society of Washington, 117(2):213-239 (2004).)

Thus, in our present-day experience, we observe that intelligent agents alone generate systems with high levels of specified complexity — such as codes and languages. When we find language-based codes in nature, we have positive reasons, based upon our uniform and repeated experience, to infer that an intelligent cause was at work.

This reasoning does not suggest ID is invoked only when something is “unknowable.” Rather, ID is invoked when something is positively “knowable” — namely when we have positive reasons to understand that intelligence is the best scientific explanation of a phenomenon.

None of this means that if we infer design, then scientists must stop trying to “understand/research some things.” The reasons for this are threefold:

First, exploring the hypothesis of intelligent design does entail seeking to scientifically “understand/research” the origin of a natural structure. If we infer design, we’re still doing research and gaining understanding of the world around us.

Second, like any scientific hypothesis, the design inference is always held tentatively, subject to future discoveries and investigations. ID is not a religious doctrine and we must always be open to new data. In that regard, ID is not stopping anyone from investigating material causes as potential explanations. In fact, the research of ID theorists has done a lot to advance our understanding of exactly what material causes like mutation and selection can and cannot do. So ID would not say we must stop investigating material causes.

This leads to my third point. Materialists commonly assert that all scientific explanations MUST rely ONLY upon material causes. (See Primer: Naturalism in Science over at the IDEA Center for a discussion.) But if ID is a scientifically investigable cause, then it is ID critics who are the ones that are closing off legitimate avenues of research and preventing scientists from invoking design where it is scientifically appropriate.

Two Extreme Positions vs. ID’s Position
So while materialists accuse ID proponents of stifling research, they are in fact the ones who are preventing science from considering certain viable explanations. Thus, in closing, there are two potential extreme positions in this debate: (A) Everything is designed and we should never invoke material causes, or (B) Nothing is designed and we must always invoke material causes.

Materialists accuse ID proponents of adopting position (A), but they are wrong. ID adopts neither extreme position. ID proponents fully acknowledge that material causes often are the best explanation of things we find in the world, but we say that science should investigate every phenomenon without prejudging the correct explanation. ID actually leads to a science without a priori restrictions or assumptions about what we must discover using the scientific method.

In contrast, materialists really do adopt extreme position (B). This makes for bad science because it presupposes the answers to scientific questions before a proper investigation is even complete.

ID rejects both extreme positions and tries to avoid assumptions about how nature ought to work. Rather, ID lets the facts speak for themselves and tries to follow the evidence where it leads. Some things may be detectably designed, and some things might have evolved by Darwinian processes or other material causes, but scientists must do the hard work and determine which explanations are warranted in which situations.

Ironically, though ID critics (wrongly) accuse ID proponents of adopting extreme position (A), ID-critics themselves often adopt extreme position (B)! Rather than ID proponents adopting an extreme position that hinders scientific progress, it is ID’s critics who are doing that by defending making methodological materialism a “ground rule” of science.