Michael Egnor wrote Materialism of the Gaps at Evolution News & Views. Quoting Egnor:
I must say that I’ve never understood the rhetorical force of the ‘God of the Gaps’ argument. The God of the Gaps sneer is invoked to imply the inexorability of materialism as a complete explanation in natural science. Any critique of materialist dogma in science from a design or immaterial perspective is derided as a 'God of the Gaps' argument. But the real issue is the gaps, which are plentiful and very wide.
Egnor puts his finger on the real issue. Perhaps he does not understand those attracted to the phrase because he does not perceive the mindless, robot-like mentality leading one to fall back on cliches. More from Egnor:
Profound skepticism for the views of opponents, combined with complacent credulity for one’s own views, is the stuff of ideological advocacy, not skepticism.
Well said Michael. Egnor quotes this gem from Dr. Novella:
My “dualism of the gaps” point, however, is that lack of complete knowledge does not justify inserting a magical answer.
Ya gotta love these materialist ideologues. Magic as in say, evoking emergence as a causal factor without being able to specify physical parameters relevant to the claim. No quantification, no demarcation of transition states, just a word- emergence. Sounds magical. But there are other magical tricks like, invoking non-existent physical mechanisms to provide a physical basis for the mind. Inserting magical answers indeed. Quoting Egnor:
Yet we know nothing — nothing — about how subjective experience could arise from matter alone. We certainly know a lot about correlations. But about causation — how matter even could cause subjective mental states — we know nothing. We don't even have a scientific paradigm by which we could even imagine what such an answer could be like. Subjective mental states share no properties whatsoever with matter. The 'explanatory gap' — our inability to explain the subjective in terms of the objective — is as wide as ever. It's infinitely wide. We don't even know where to begin to answer the question 'how does subjectivity arise in association with matter' from a materialistic standpoint.
Dr. Novella is wrong to attribute the inference to dualism to an argument from ignorance. The exact opposite is true. The reason that immaterial causation is invoked to explain the mind is because we know so much about the mind and about the brain, and it’s evident to most people (that is, people who aren’t dogmatic materialists) that the mind isn’t material. It isn’t an argument from ignorance. It’s an argument from deep knowledge — deep knowledge of the mind and of the brain. The invocation of immaterial causation for aspects of mental states is the result of our deep knowledge of the difference between mind and matter.
I would add one more thing. The reason why material causation is not invoked for behavioral studies, tracing causation to decisions, is that such speculation is superfluous to the results cited. Vacuous add ons.