The term pseudoskepticism (or pseudoscepticism) denotes thinking that appears to be skeptical but is not. The term is most commonly encountered in the form popularised by Marcello Truzzi, where he defined pseudoskeptics as those who take "the negative rather than an agnostic position but still call themselves 'skeptics'". University of Washington electrical research engineer William J. Beaty describes pseudo-skepticism as;
Arizona State University instructor Rochus Boerner describes pseudoskeptics as disbelievers, rather than nonbelievers, "characterized by an a priori belief that a certain idea is wrong", a view shared by Princeton physicist Gregory N. Derry describing Creation Scientists' skepticism of science as ".. selected pseudoskepticism directed towards any ideas that disagree with their preconceived conclusions.
The term pseudoskepticism was popularised and characterised by Truzzi, in response to the skeptic groups who applied the label of "pseudoscientists" to fields which Truzzi preferred to describe as protoscience.
While a Professor of Sociology at Eastern Michigan University in 1987, Truzzi gave the following description of pseudoskeptics in the journal Zetetic Scholar which he founded:
Truzzi attributed the following characteristics to pseudoskeptics:
Truzzi's argument begins with the premise that if a phenomenon has not been proven, this does not imply that it has been disproven. But Truzzi went further, holding that if a phenomenon had not been disproven, this implies that it is plausible, and that anyone who does not consider both options equally, is a pseudoskeptic. Truzzi wrote:
It is common for fringe theorists and practitioners to apply the label pseudoskeptic to anyone who is prepared neither to investigate a claim nor to accept its conclusion. This is a misunderstanding of the scientific method. Consider, for example, a test that is performed showing apparent evidence for extrasensory perception (ESP). Based on experience of similar 'results', most scientists will suspect a flaw in the test. Scientific practice does not require every scientist to fully vet every experiment performed by every other scientist. Rather, scientific reports are reviewed by a number of peers, and where an experiment has produced interesting results, other scientists will try to reproduce it. If their results match, the evidence is accepted. If not, the original result is agreed to be an anomaly and it does not affect the acceptance of the dominant theory. To state that there must be a flaw in a test without relying on other tests would be pseudoskepticism; taking a position on the validity of the test does require accepting a burden of proof. But simply choosing to ignore the test or declaring it to be an anomalous result due to a contradiction to other tests is not pseudoskepticism, however frustrating it can be to those who welcome the apparent result of a test.
A Spring 2006 course at the University of Colorado, "Edges of Science", promised to examine "the evidence for paranormal phenomena, [and] reasons for skepticism", including a section which shows "how a healthy skepticism can see through unsupported assertions, and how pathological skepticism can work against honest scientific inquiry."
Pennsylvania State University Folklorist David J. Hufford uses the term "radical skepticism" to describe the unexamined prejudices and preconceptions which he argues are embraced by many — perhaps most — academic scientists. After reading and analysing the works of many skeptics and debunkers, Hufford argues that one can readily find:
L. David Leiter, a member of the fringe Society for Scientific Exploration, uses the terms 'pseudo-skepticism' and 'pathological skepticism' to refer to "organized skepticism", specifically the "Philadelphia Association for Critical Thinking" (PhACT), "[i]nstead of becoming scientifically minded, they become adherents of scientism, the belief system in which science and only science has all the answers to everything" and that even many pseudoskeptics are unwilling to spend the time to "read significantly into the literature on the subjects about which they are most skeptical".
Prof. Hugo Meynell from Department of Religious Studies at the University of Calgary, labels as 'pseudo-skepticism' the "extreme position that all significant evidence supporting paranormal phenomena is a result of deception or lies". Psychiatrist Dr. Richard Kluft, MD has noted that:
Parapsychologist Susan Blackmore described the "worst kind of pseudoskepticism":
Commenting on the labels "dogmatic" and "pathological" that the "Association for Skeptical Investigation" puts on critics of paranormal investigations, Robert Todd Carroll of the Skeptic's Dictionary argues that that association "is a group of pseudo-skeptical paranormal investigators and supporters who do not appreciate criticism of paranormal studies by truly genuine skeptics and critical thinkers. The only skepticism this group promotes is skepticism of critics and [their] criticisms of paranormal studies."
Prior to Truzzi, the term "pseudo-skepticism" had occasionally been used in 19th and early 20th century philosophy.
Professor of Philosophy at the University of Illinois, Frederick L. Will used the term "pseudo-skepticism" in 1942. Alasdair MacIntyre writes:
Notre Dame Professor of English, John E. Sitter used the term in 1977 in a discussion of Alexander Pope: "Pope's intent, I believe, is to chasten the reader's skepticism — the pseudo-skepticism of the overly confident 'you' ...
Science writer C. Eugene Emery, Jr. compared the degrees of skepticism of CD-ROM-based encyclopedias of articles on pseudoscientific subjects. He called such articles "pseudoskeptical" if they only suggested or stated that the subject was "controversial, but the author may not have a clue as to why".