Cranial capacity and bias of scientists

Diane Paul got me to look at Lewis et al’s critique of S. J. Gould’s account of Morton’s measurement of cranial capacity of different peoples (races) and at Weisberg’s careful, but not-well-known response. Lewis et al. has been widely cited as a takedown of Gould. What follows is my capsule summary of issues:

1. Gould attempted to show that Morton was unconsciously biased primarily because his first measurements with the seed were low for native americans — measurements that Morton, as a good scientist, replaced by more objective data (measurements using shot).
2. Morton was uncritical of all kinds of stereotypes of races, then, as a scientist, promoted these to the audience.
3. Lewis et al. miss the primary point of Gould (#1), focusing reader’s attention on a non-issue, namely, that Morton’s shot measurements were accurate.
4. Without the shot-measurement-accuracy issue, the rest of Lewis et al.’s reworking of Gould’s reworking of data wouldn’t have been much of a contribution — indeed, Weisberg counters most of their points.
5. Similarly, Gould’s reworking of other aspects of Morton’s data analysis wouldn’t have been much of a contribution, EXCEPT for Morton’s lack of correction of the data for different ratios of male:female skulls. (Because females are on average smaller, if one people is represented by more female skulls than another, it will have a lower average cranial capacity.)
6. Lewis et al. want to use their account to defend science (especially physical anthropology), while allowing scientists to be biased. That is because science corrects itself.
(Problems with this view:
Corrections in science are done — or not done — by scientists.
Gould is also a scientist.
What accounts for science/scientists getting it wrong for a while [and thus the science needing correction]?
How can scientists at any point of time know that the corrections for bias-in-the-past have all been made?
How long did it take for the sexual dimorphism issue [#5] to be corrected for?)
7. If Lewis et al. were right that Gould not Morton were biased in the analysis of the cranial volume data, then they have shown that a scientist can be biased. (Admittedly, a scientist who is also making interpretations of science, but so, albeit less self consciously, they are also making interpretations of science.) In any case, are Lewis et al. agreeing with Gould’s main point, namely that scientists can be biased?
8. My guess is that Lewis et al. would respond to #7 by saying that Gould is not being a scientist, but is being an ideologue, in his re-analysis of Morton. After all, Gould admits his formation on the left. But then Morton gives us lots of evidence of his being an exponent of emergent scientific racism (see #2). Symmetrically, Lewis et al. ought to be skeptical of Morton’s science.
9. Now, Morton’s scientific racism may have seen unobjectionable to many of his readers. In this vein, i.e., looking for the spirit of the time among many contemporary readers, the positive reception of Lewis et al. by the media and the blogosphere invites interpretation.

Gould, SJ (1981). Mismeasure of Man. New York: Norton & Company
Lewis J. E. et al. (2011) “The Mismeasure of Science: Stephen Jay Gould versus Samuel George Morton on Skulls and Bias.” PLoS Biol 9(6): e1001071.

Weisberg, Michael (2015). “Remeasuring Man.” Evolution & Development 16 (3): 166–178.


2 thoughts on “Cranial capacity and bias of scientists

  1. John

    How is the accuracy of Morton’s measurements a non-issue? Morton became frustrated with the inaccuracy of the measurements of cranial capacity using seeds so he switched to a more accurate method using shot. How is it a scientist recognizing experimental error and correcting is given as evidence for the absence of scientific objectivity?


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