There seem to be several questions packed into this post. From the philosophy of mind point of view, please refer to the extensive literature on Dualism vs Materialism. Musolino isn't the first to delve into this question. Note that I am conflating the position that souls exist with substance dualism, even though strictly speaking they are not the same.
The philosophy of science questions implied by this post are much more interesting, and I will try to breakdown my reading of the post:
[...] Musolino's book “The Soul Fallacy” in which he claims that the scientific consensus is that the soul does not exist.
Is his view correct?
- How do we know what the scientific consensus on given question is, and what is the scientific consensus on the existence of souls?
The social epistemology of science. Are surveys enough? Consider the following question pertinent to another big debate: How do we know that the scientific consensus is that climate change is real, especially given that many non-scientists frequently challenge that this is indeed the consensus? We can apply the methodology from that field to the question of the soul as well, assuming such data exists. See this study.. In particular, the following passages is relevant:
These kinds of reports and statements are drafted through a
careful process involving many opportunities for comment,
criticism, and revision, so it is unlikely that they would diverge
greatly from the opinions of the societies’ memberships. Nevertheless,
it could be the case that they downplay dissenting
opinions. One way to test that hypothesis is by analyzing the contents
of published scientific papers, which contain the views that are
considered sufficiently supported by evidence that they merit
publication in expert journals. After all, any one can say anything,
but not anyone can get research results published in a
refereed journal. Papers published in scientific journals must
pass the scrutiny of critical, expert colleagues. They must be
supported by sufficient evidence to convince others who know
the subject well. So one must turn to the scientific literature to
be certain of what scientists really think. Before the twentieth century, this would have been a trivial task. The number of scientists directly involved in any given debate was usually small. A handful, a dozen, perhaps a hundred,
at most, participated—in part because the total number of scientists in the world was very small (Price 1986). Moreover, because professional science was a limited activity, many scientists used language that was accessible to scientists in
other disciplines as well as to serious amateurs. It was relatively easy for an educated person in the nineteenth or early twentieth century to read a scientific book or paper and understand what the scientist was trying to say. One did not have to be a scientist to read The Principles of Geology or The Origin
of Species. Our contemporary world is different. Today, hundreds of
thousands of scientists publish over a million scientific papers
each year. [...] No individual could possibly read all the scientific papers on a subject without making a full-time career of it. Fortunately, the growth of science has been accompanied by the growth of tools to manage scientific information. One of the most important of these is the database of the Institute for Scientific Information (ISI). In its Web of Science, the ISI
indexes all papers published in refereed scientific journals every year—over 8,500 journals. Using a key word or phrase, one can sample the scientific literature on any subject and get an unbiased view of the state of knowledge.
We can perform a similar experiment now: ScienceDirect is a well known scientific publisher and research paper database (although a lot of the access is behind a pay wall, most people affiliated with a western university have access to it). A search for the term "Soul" in their database yields some examples:
Someone who is serious about assessing the scientific consensus on the existence of soul would have to go through such databases (there are many, scholar.google.com should help as well), and then run some statistics and summarize their findings. This would be more accurate than a simple survey.
- Can science disprove the existence of souls?
Science can never disprove the existence of souls: Following the problem of induction and Popper's falsificationism, 10 000 000 observations of white swans doesn't prove that black swans don't exist, and logically speaking, there is always a small chance that one day we might come across a black swan. Similarly, the best science can do is say that no experiment has ever proved that souls exist, but it can never prove definitively that souls don't exist, there is always a chance, no matter how small, that some day, an new unheard of experiment that proves the existence of souls.
All of this presupposes that the soul can submit to scientific (i.e. physical, experimental) methods in the first place. Which leads us to the next question:
- Is the the existence of the soul a scientific question?
I will set aside the demarcation problem and the issue of which questions are scientific and which questions are not, and work with a naive empiricist notion of "scientific question = one that can be resolved by experiments and observations, i.e. empirical evidence".
The thing is, almost all arguments for dualism revolve around proving that the empirical description of mental phenomenon is incomplete, then rely on other epistemic methods (rationalists arguments, the immediacy of subjective experience, etc...) to fill the gap left by the incompleteness of empiricist methods. Since mental phenomena cannot be described using strictly empiricist methods, they must be non-physical in nature, hence dualism.
Here's another way of putting it: The central premise of dualism is that the mind or the soul is non physical. If it is non physical, then physical methods of investigation don't apply, other methods have to be used.
Consider one of the main contemporary arguments for dualism, Frank Jackson's Knowledge argument: Mary the Neuroscientist knows all the physical facts about the color red, but her knowledge of the color red is incomplete.
Similarly, DesCartes argument for dualism and Saul Kripke's modern variation on it are rationalist arguments (in the sense of the rationalism vs empiricism debate), whose starting point is the incompleteness of the empirical description of mental phenomena.
The only way then for the question of the existence of the soul to be a scientific question is if one concedes that not all scientific knowledge is empirical. But most scientists don't: As pointed out in the accepted answer to the question linked to in the OP: "The operational consensus of physical scientists is that physicalism holds. That is, experiments are planned and executed as if physicalism is true."
So it really does come down to the demarcation problem: If you stick to a strictly empiricist definition of scientific knowledge, as most modern scientists do, then the question is not a scientific one.
One final (somewhat silly) note: Various sci-fi and fantasy scenarios involve protagonists using special devices to detect and measure supernatural phenomena (for example Ghostbuster's PKE Meter), which seem to indicate that physical devices might be used to measure non-physical entities such as souls. On the highly unlikely chance that someone was to somehow physically detect souls (say for example as something leaving the body at the moment of death) - this wouldn't mean that physical devices can measure non-physical entities. Instead this would mean that souls are physical (again very, very, vey unlikely) and we need to reexamine the laws of physics and biology.
