Testimony of an insider

Warren B. Hamilton, PhD, Geology, is Distinguished Senior Scientist, Department of Geophysics, Colorado School of Mines.  For 43 years he worked at the U.S. Geological Survey.  He was an author in over 100 refereed articles from the 1950s to the present, and in 1989 he received the Penrose Medal, the Geological Society of America's highest award.

Professor Hamilton believes in plate tectonics, but has come to realize that a generally accepted component of the theory, mantle plumes, is wrong.  The opposition he witnessed to any challenge to plumes exposed an ugly side of the academic geology world that many are unaware of.  Here are extended excerpts, with clarification, from the end of a 40 page essay on upper-mantle circulation (Hamilton, 2002), the perspective of a man with exceptionally long experience in the field, the testimony of an insider:


This essay has evaluated many mutually incompatible concepts, argued that broad or specialist consensus often is mistaken on fundamental aspects of Earth properties and behavior, and sought a unifying new synthesis.  Majority opinion usefully constrains concepts only when it is broadly informed, flexible, and open to challenge -- yet today's procedures defend entrenched assumption and delay challenge and progress.  Much geoscience education is narrow and inculcates its trainees with current paradigms, and most new scholars are equipped to solve the minor problems those paradigms define but not to seek fresh approaches.

Different rules of evidence apply to conventional wisdom (evaluation is not necessary) than to a challenge to conventional wisdom (proof must be overwhelming before discussion is warranted).  Appalling papers in support of plumes are now being published in major journals, perhaps indicating that pro-plume reviewers who approve them welcome any debris with which to heighten the defensive rampart against a paradigm shift.

Evidence available from the continents before 1940 required continental drift.  Much more was available by 1960, yet only in the late 1960s, when evidence from the ocean floors for the spreading-and-subduction mechanism for drift abruptly became overwhelming, did majority opinion begin to waver.  Throughout the era of increasing quality and quantity of evidence, most geoscience leaders, and following them most other scientists, not only were unwilling to examine this evidence but often obstructed publication by those who did study it.  Phenomenological geophysicists finally provided the conclusive marine and seismological evidence.

Most geoscientists now active came on the scene when this was history, but there is much to learn from that history, for similar retardation of progress is widespread today.  As before, the value of work by many specialists is negated by misconceptions that could easily be corrected by incorporating empirical knowledge rather than by working from uninformed assumptions.  As before, there is conflict between establishment theorists (e.g., data must be force-fit to hypothetical plumes) and a few empiricists (plumes are disproved).  As before, suppression of dissent is common.  I know of many recent examples wherein prominent members of the dominant pro-plume community have stifled anti-plume reports and research.  Although such perpetrators might tell themselves that they are maintaining professional standards, bad science is to them anything contrary to their own conjectures.  (I have been guilty of this myself in other contexts)  A friend terms peer review "the great leveler": it filters out the worst and the best, and leaves the broad middle.  The many reviewers who block papers by, and grants to, those who hold contrary views are proper subjects for sociologists who claim that "science is merely a game for distributing prestige and grants among competing players" (Jones, 1999).

Widely accepted assumptions regarding the composition, evolution, and behavior of the mantle appear to be in error, yet evaluation of alternatives is actively discouraged.  Plumology exemplifies mistaken dominant opinion analogous to the dogma of permanent continents and oceans, and similarly retarding of progress.  The present enthusiasm for fixed plumes, like that for stabilism during the middle half of the 20th century, represents groupthink that is easily falsified and yet is impervious to evidence.  Believers attribute miracles to plumes and make their assumptions and rationales ever more complex to encompass all facts, no matter how incompatible with prior assumptions, in order to insulate conjecture from test.  Unquestioning acceptance of these speculations in geodynamics, tectonics, and petrology leads to much further work of dubious value.  Our being scientists confers no infallibility upon us, and our egos often lead us astray.

Most geoscience is done by interpreting the parts in terms of the assumed whole.  Basic assumptions often are so entrenched that practitioners are unaware that there might be little or no evidence behind them.  Data, narrowly sought and interpreted, fill the space between starting assumptions and conclusions required by them.  Incremental advances within specialties are made mostly by this method.  Grant-giving agencies require this method in proposals, and peer reviewers of proposals and manuscripts commonly enforce it, thereby ensuring that most advances are small.  The method is no stronger than the premises at issue and hence impedes major advances, for adaptation to incompatible data is made by increasing complexity of assumptions rather than by seeking alternatives.  Geophysical modeling wherein only parameters that permit plumes are considered, and ever-more-convoluted plume speculations, exemplify such shortcomings.  Reviewers and grantgivers who insist that new work consist mostly of gathering data by means, and for purposes, detailed in advance minimize the value of much research.

Major advances in science come mostly from the opposite process, interpreting the whole in terms of the parts.  Recognize a problem, gather information, evaluate conflicts between concepts in diverse fields, and seek explanation and understanding.  New or revised concepts should themselves be subject to constant scrutiny as new data come in and as other disciplines provide data for challenge.  The plate-tectonics breakthrough of the late 1960s exemplified such methodology -- and yet much nowadays written under the banner of plate tectonics is deduced from false premises.

Overspecialization is a large part of the problem.  Work in some specialties loses much value because primary data disprove their basic assumptions.  Plumology could not have gained its present wide following had more in the geoscience community been aware of seafloor-spreading constraints.  Geochemists would not enthusiastically support plumology were more of them cognizant of petrology -- and this problem worsens as geochemistry expands at the expense of petrology in most universities.  Modelers of convection are unaware of elementary plate tectonics and do not realize they provide no explanation for plate motions.  Specialists increase their isolation, and thus limit their own work, by favoring insiders for jobs, grants, and publications, excluding outsiders by writing in jargon, and fiercely defending their groups against challenges to their beliefs.  Multidisciplinarity is lauded only as an abstraction, and reviewers take views so narrow that new approaches have trouble finding homes.  The routine sending, by editors and managers, of manuscripts and proposals to established experts in specialist fields at issue too often results in approval of papers with which the reviewers agree, and in rejection of viable new but controversial concepts and of the data that support them.  Cloning results when hirings and promotions are based on recommendations by such experts.

We would all rather be right than wrong, yet science advances primarily when many of us are proved wrong.  Breakthroughs by definition surprise most people.

* * * * * * * *

Warren B. Hamilton. 2002. The Closed Upper-Mantle Circulation of Plate Tectonics, in Plate Boundary Zones, American Geophysical Union Geodynamics Series Volume 30, eds. Seth Stein and Jeffrey T. Freymueller, pp. 359-410.

David Jones. 1999. Citing to infinity. Nature, Vol. 402, p. 600.


To my knowledge, Professor Hamilton is not aware of, nor supports, the Shock Dynamics geology theory.

John Michael Fischer, 2006