Historical Reconstruction: Gaining Epistemic Access to the Deep Past

Abstract

We discuss the scientific task of historical reconstruction and the problem of epistemic access. We argue that strong epistemic support for historical claims consists in the consilience of multiple independent lines of evidence, and analyze the impact hypothesis for the End-Cretaceous mass extinction to illustrate the accrual of epistemic support. Although there are elements of the impact hypothesis that enjoy strong epistemic support, the general conditions for this are strict, and help to clarify the difficulties associated with reconstructing the deep past.

Paleontology: Outrunning Time

“…Wimsatt (1981Wimsatt ( , 1987 has not written extensively on epistemic issues in the historical sciences, but his remarks on robustness analysis are a helpful adjunct to discussions of consilience. Forber and Griffith (2011) emphasize the epistemic support garnered by independent lines of evidence that do not overlap (or overlap as little as possible) in their auxiliary assumptions, as each line of evidence will be somewhat immune to criticisms leveled against another line. Yet Wimsatt's concept of robustness emphasizes the extent to which certain derivations will be relatively insensitive to the particular auxiliary assumptions made.…”

“…Forber calls this type of underdetermination contrast failure and leaves open the possibility that the condition may be temporary. Forber and Griffith (2011) focus on the issue of epistemic access to the past. They emphasize that one way to gain epistemic access to the past is to, in a sense, triangulate on an estimate of a particular quantity by utilizing evidentiary inferences starting from independent bodies of evidence and sharing as few auxiliary assumptions as possible.…”

“…The estimation of the age of a stratum from growth bands in one of its contained fossils relies on a set of auxiliary assumptions completely independent from those of radiometric dating (paleoastronomy based on invertebrate fossils and that based on rhythmites do share at least one auxiliary assumption in common-the constancy of Newton's universal gravitational constant G [Mazumder and Arima 2005]). In any case, to the extent that past dates can be estimated by multiple means whose auxiliary assumptions differ substantially, or are entirely independent, the resulting date garners the evidential support conferred by a consilience of inductions (Whewell 1858;Wimsatt 1981;Forber and Griffith 2011).…”

How to Study Adaptation (and Why To Do It That Way)

“…If a given pattern has an adaptive cause then by definition at some time in the past, not just the observable present or moments captured in fossil traces, heritable variation with fitness consequences was present (Leroi et al 1994;Forber and Griffith 2011). Selection on this variation is assumed to have led to the pattern observed today ( Figure 3B).…”

“…When the available data are unable to distinguish convincingly between two or more hypotheses, the hypotheses are said to be underdetermined by the data (Ladyman 2002;Dietrich and Skipper 2007). The literature on adaptation is full of examples of underdetermination (Forber 2009). For example, carrion flowers might have been favored in an environment with a dearth of bees and an abundance of flies.…”