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One problem may be our (mostly implicit   This emergent trend in earth sciences   REFERENCES CITED
         but still pervasive) attachment to the princi-  reflects the maturing of the discipline from   Ablowitz, R., 1939, The Theory of emergence: Phi-
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         1993). Uniformitarianism was very useful   way  to  better  calibrate  our intuition  for   10.1130/G47417.1.
         when eighteenth- and nineteenth-century   emergence, as well as to test if a geological   Gerya, T., 2019, Geodynamics of the early Earth:
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         with clergy claiming it was 6,000 years old,   behavior and what are the main physical   p. 1006–1007, https://doi.org/10.1130/focus102019.1.
         but that was then, and this is now. Does our   parameters controlling it.  Gerya, T., Stern, R.J., Baes, M., Sobolev, S., and
         allegiance to the old philosophy stop us from   We think that encouraging thinking about   Whattam, S., 2015, Plume-induced subduction
         addressing questions that need to be asked?  the  role  of  emergence  in  all  earth  systems   initiation triggered plate tectonics on Earth: Na-
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          Gould (1965) distinguished substantive     should be part of the way for the geosciences   nature15752.
         and methodological uniformitarianism. Sub-  to advance in the twenty-first century. The   Golabek, G.J., Keller, T., Gerya, T.V., Zhu, G.,
         stantive uniformitarianism considers that   field of emergence is much broader than the   Tackley, P.J., and Connolly, J.A.D., 2011, Origin
         ancient Earth processes (e.g., orogeny, sedi-  earth sciences, with entire institutes study-  of the Martian dichotomy and Tharsis from a
         mentation, erosion) were the same as now   ing a wide range of emergent phenomena; for   giant impact causing massive magmatism: Ica-
         operating. In contrast, methodological unifor-  example, the Santa Fe Institute, https://www   rus, v.  215, p.  346–357,  https://doi.org/10.1016/
         mitarianism states the obvious: that the laws   .santafe.edu/about. At present, the emergence   j.icarus. 2011.06.012.
         of physics and chemistry pertain to all of   of planetary tectonic styles is not being con-  Gould, S.J., 1965, Is uniformitarianism necessary?:
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         Earth’s history. Gould (1965) concluded that   sidered by these researchers, and it should   https://doi.org/10.2475/ajs.263.3.223.
         substantive uniformitarianism was “…false   be. How can we help make this happen? A   Lenardic, A., 2018, The diversity of tectonic modes
         and stifling to hypothesis formation…” and is   good first step would be for more geoscien-  and thoughts about transitions between them:
         “…an incorrect theory [that] should be aban-  tists to learn about emergence; the Wikipedia   Philosophical Transactions of the Royal Society
         doned” (p. 223). There is still an important   entry “emergence” is a good place to start.   A, v. 376, https://doi.org/10.1098/rsta.2017.0416.
         role for substantive uniformitarianism in our   Second steps include teaching about emer-  Morowitz, H.L., 2002, How the World Became Com-
         efforts to reach and teach students and the   gence in our classes and considering it in    plex: The Emergence of Everything: Oxford, UK,
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         public. Perhaps in 1965 it appeared that the   our research.           Pines, D., 2014, Emergence: A unifying theme for
         battle with creation pseudoscience was over,   Embracing emergence for understanding   21st century science: Foundations and Frontiers of
         but not in 2020, at least in the United States.   Earth’s history not only can inject excite-  Complexity, v. 28, no. 2, https://medium.com/ sfi
         Substantive uniformitarianism is still useful   ment into our science, the philosophy can   -30-foundations-frontiers/emergence-a-unifying
         for teaching lower-division undergraduates   pay psychic benefits. We are facing a very   -theme-for-21st-century-science-4324ac0f951e
         and in battles with creationists, for example,   uncertain future, but thinking about emer-  (accessed 10 Sept. 2020).
         to show why and how the Grand Canyon was   gence can perhaps reassure us that all   Stern, R.J., 2018, The evolution of plate tectonics:
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         River flowing through a plateau lifted up by   futures are uncertain except for low-energy   Tackley,  P.J.,  2000,  Self-consistent  generation  of
         mantle convection, not in a few days by   systems  (e.g., dead planets  and dead peo-  tectonic plates in time-dependent, three dimen-
                                             ple). Which would you rather be part of, a
         Noah’s flood. But within the scientific com-                             sional mantle convection simulations Part 1:
         munity, substantive uniformitarianism poi-  low-energy system with a certain future or   Pseudo-plastic yielding: Geochemistry, Geo-
         sons scientific discussions about how plate   a high-energy system with an unpredictable   physics, Geosystems, v. 1, no. 8, https://doi.org/
         tectonics came to be Earth’s dominant con-  future but with the promise that something   10.1029/ 2000GC000036.
         vective mode.                       will emerge, some time in the future? We   Windley, B.F., 1993,  Uniformitarianism today:
          Modern earth sciences use methodologi-  know which planet we want to be on!   Plate tectonics is the key to the past: Journal of
         cal uniformitarianistic approaches for both                              the Geological Society, v. 150, p. 7–19, https://
                                                                                  doi.org/10.1144/gsjgs.150.1.0007.
         discovering  and  understanding  emergence   ACKNOWLEDGMENTS
                                              Thanks to Pete DeCelles and an anonymous ref-
         based on numerical modeling that uses fun-  eree for constructive comments and suggestions.   Manuscript received 23 July 2020
         damental physical laws for investigating   This is University of Texas at Dallas geosciences   revised Manuscript received 20 aug. 2020
         behavior of complex geological systems.   contribution #1373.          Manuscript accepted 6 sept. 2020













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