It’s not clear to me what Pigliucci’s suggested Bayesian approach to the demarcation problem is. He says something to the effect that those who adjust their probabilities in accordance to the evidence are doing science, and those who don’t aren’t. But that leaves open the question of what counts as evidence and whose evidence counts, and may entail that some scientists aren’t doing science and some pseudoscientists are.
The philosopher Philip Kitcher, in his book _The Advancement of Science_, proposed that the science/pseudoscience distinction bestreduces to a scientist/pseudoscientist distinction, in that scientists are those who participate in the community of scientists and do work recognized as science by scientists, while pseudoscientists don’t. Pigliucci’s view, on one possible interpretation, seems similar.