The concept of paradigms is a recurrent topic in this report. In some respects I am as much interested in how we think as to what we think about deglacial history. In the Preface to this report I stated: “Paradigms are powerful ways of processing information, at the very heart of human thinking. But at times they limit our ability to see and understand what is before our eyes.” I am convinced that paradigms are profoundly important in the deciphering of deglacial history, that the past thinking of the deglacial history of Vermont reflects paradigm-ic biases, just as this report so too reflects paradigm-ic thinking. Paradigms are unavoidable ways of thinking. We all use them, succeed with them when we solve a history puzzle about a long ago time, and as well are trapped by them, generally without our being aware of their being a part of our thinking.
We can see the paradigm-ic model underlying the thinking of Stewart and MacClintock with their perception of flow directions as the basis for historical deduction. Chapman’s maps of Coveville, Fort Ann, and Champlain Sea, showing the progressive positions of the associated ice margins reflects his paradigm-ic preconception that the recession of the ice sheet generally was northward. Parent et Occhietti, who have been very bold in exploring deglacial history, and have been quite helpful to me, helping me see new ways of thinking about these matters, nevertheless have their own paradigm-ic constructs. As discussed elsewhere herein this is reflected in their positioning of the northern margin of their Lake Candona (Fort Ann in Quebec), not so much based on data but by inference, which is to say the way they think about ice margin recession. We all of us have no choice but to do as best we can, sort of like looking at our Bath Tub or whatever model we are using, forcing us to blink our eyes to try to then look once again at the data before us with fresh eyes.
These observations are not meant to be critical or judgmental or fault-finding. We all of us by our nature are trapped by the ways our brains our wired to process information, in this case the interpretation of deglacial history. Franzi’s recent revision of the Champlain Basin water body history, with his recognition of the variable and diachronic nature of strandlines is an example of his coming to realize that our (meanng all of us) way of thinking about these strandlines as timelines has been incorrect, (meaning all these years since Chapman first opened our eyes to this subject in the late 1930s). Franzi introduces a “paradigm shift,” the full implications of which have yet to be explored.
For me, I too have struggled to overcome my paradigm-ic preconception about the nature of ice sheet margins and their recession. In the past I tended to think of ice margins as relatively simple, solid boundaries, like simple lines on a map, which receded progressively northward. As my examination of the evidence on VCGI progressed and my information gathering continued, I began to encounter difficulties that forced me to challenge my mental model, to see other possibilities. I now recognize that ice margins were not like simple lines on maps, and the northward recession likewise was not so simple. It was only late in the writing of this report that I began to see the evidence differently. In fact, report writing and head scratching became intertwined and more protracted, requiring multiple report revisions.
Deciphering deglacial history, it turns out, is not a simple proposition, sort of like analogous to the lining up rubber duckies in single file in a bathtub, so to speak. If an analogy is to be made with the Bath Tub Model it entails both spatial and temporal variations, which goes way beyond simple rubber duckie type thinking. Whereas the recession of the ice margin in the Champlain Basin in Vermont was both south to north and east to west in Fort Ann time, so too the ice margin receded to extend the Fort Ann (Lake Candona) corridor into Quebec, presumably expanding progressively eastward along the Quebec Piedmont until the ice sheet opened to allow the corridor to drain. This presumably took place in Vermont after T7 time but before T8 time, with early delta formation in the Missisquoi Basin at the Champlain Sea marine limit level before a readvance in T8 time. The extent of the recession prior to T8 time, meaning the position of the ice margin at maximum recession, or in other words the extent of the readvance in T8 time, is as yet unknown. However, the absence of Fort Ann deltas on the north side of the Missisquoi Basin, which was noted by Wagner (1972) and previously by Cannon, suggests that the magnitude of the recession may have been quite limited. However, to further complicate matters, if these deltas are in fact absent owing to the ice sheet presence, then how did Lake Candona extend further east along the Quebec Piedmont? This conundrum is very much like the question posed above having to do with how the ice sheet could be standing at Starksboro as required for the Bristol delta in Coveville time yet as well necessarily be north of the South Hinesburg to allow for the Coveville delta at that location in Coveville time. The answer, I suggest, lies in the nature of ice margins which were far more complex than our simple mental models imagine. In order to get out of my paradigm box I had to find a “dissaggregated labyrintihian complex in a narrow more or less open water corridor,”which came not from my imagination but from very recent literature about the nature of ice margins.
Paradigms are wonderful mental tools that help us think… way beyond the capacity of Artificial Intelligence (at least so far) but they also can be traps. 1 According to ChatGPT, “I can identify patterns in reasoning, language, and assumptions that signal a certain worldview or theoretical framework, whether its scientific, cultural, political, or philosophical.” ChatGPT has not learned to be modest. I do not believe it has the capability, yet, of discarding one worldview for another, or evaluating the merits of doing so. Nor does it have imagination. It should be clear by now that the point to this discussion is that, not just in my opinion but as well some of the great philosophers of scientific thinking, we are all confronted by challenges to our paradigm-ic thinking. Paradigms represents traps which make it difficult to see the “forest for the trees,” as the saying goes. Whereas I would like to think that this report breaks through some of these constraints (which was not my initial goal), it is likely that these have not been fully resolved, and that it remains to future generations to further advance our understanding, which I believe will entail collaborative thinking by researchers in Vermont, New York, Quebec, New Hampshire, and perhaps beyond.
I added the word “Blinders” to the heading for this section of the discussion underscore that paradigms can be so deeply imbedded as to prevent us from looking at deglacial history in new and different ways. This is especially the case for the concept of the “Bath Tub Model.” In fact, for one of the reviewers of early drafts of this report, the suggestion of this model seemed so preposterous and outrageous as to angrily lash out at me for not understanding the nature of glaciers and ice sheets. Perhaps for some readers of this report, this concept will prove to be a bridge too far. As I said, the best I can do is make my case, which has only grown stronger and for me more convincing since that early draft, as history will ultimately be the judge.
Footnotes