Starting with Strassfeld's version as of May 27 (hand-correcting for a few errors reported by Jennings and correcting a few more errors that I independently found), I decided to chart the percentage of women faculty in these departments over the period in question. (Here are my raw data. Corrections welcome. Data of this sort are rarely 100% perfect. The general trends, however, should be robust enough that a few errors make no material difference.)
I looked at time course by taking a snapshot of the faculty every five years starting in 1930 (ending in 1979 rather than 1980). Here's a chart:
UPDATE 2:04 p.m.: Strassfeld has made some further corrections and created this year-by-year chart:
* The 1930, 1935, 1940, and 1945 snapshots contain exactly zero women faculty (compared to 63-71 men during the period).
* The 1950 and 1955 snapshots contain exactly one woman: Elizabeth Flower at Penn (the universities have 98 and 104 recorded men faculty in those years).
* In 1960, Flower is joined in the dataset by Mary Mothersill at Chicago. The 1965 and 1970 snapshots both show five women (3%) among 156 and 191 total faculty respectively.
* In the late 1970s there's a sudden jump to 16/174 (10%) in 1975 and 18/171 (12%) in 1979.
Thus, despite the presence of some highly influential women philosophers in the early to mid 20th century -- for example, Simone de Beauvoir, G.E.M. Anscombe, and Hannah Arendt -- women held a vanishingly tiny proportion of philosophy faculty positions at elite U.S. universities from the 1930s through the early 1960s, even fewer than one might be inclined to think, in retrospect, upon casual consideration.
Some reference points:
* Using data from the National Center for Education Statistics, I estimated 9% women faculty among full time four-year university faculty in the U.S. in 1988 and 12-20% in the 1990s.
* Jennings and I found about 25% women faculty in PGR-rated U.S. PhD-granting departments in 2014.
I find this a helpful reminder that, for all of the continuing gender disparity in philosophy in the 2010s, things are nonetheless much different from the 1950s. Try to imagine the gender environment that Flower and Mothersill operated in!
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I am also reminded of this autobiographical reflection from Martha C. Nussbaum, from her 1997 book Cultivating Humanity:
When I arrived at Harvard in 1969, my fellow first-year graduate students and I were taken up to the roof of Widener Library by a well-known philosopher of classics. He told us how many Episcopal Churches could be seen from that vantage point. As a Jew (in fact a convert from Episcopalian Christianity), I knew that my husband and I would have been forbidden to marry in Harvard's Memorial Church, which had just refused to accept a Jewish wedding. As a woman I could not eat in the main dining room of the faculty club, even as a member's guest. Only a few years before, a woman would not have been able to use the undergraduate library. In 1972 I became the first female to hold the Junior Fellowship that relieved certain graduate students from teaching so that they could get on with their research. At that time I received a letter of congratulation from a prestigious classicist saying that it would be difficult to know what to call a female fellow, since "fellowess" was an awkward term. Perhaps the Greek language could solve the problem: since the masculine for "fellow" was hetairos, I could be called a hetaira. Hetaira, however, as I knew, is the ancient Greek word not for "fellowess" but for "courtesan."
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Note 1 (added 11:47 a.m.): This list is drawn from Strassfeld. He explains his selection thus:
I determined which departments to survey recursively, defining the "leading departments" as those whose graduates comprised the faculties of the leading departments. Focusing on the period of 1945-1969, when universities were growing explosively, I found that there was a group of eleven philosophy departments that essentially only hired graduates from among their own ranks and foreign universities - that it was virtually impossible for graduates of any American philosophy departments outside of this group to gain faculty positions at these "leading departments." Indeed, between 1949-1960, no member of their faculty had received a Ph.D. from an American institution outside of their ranks. There were, of course, border cases. Brown, Rockefeller, MIT, and Pittsburgh in particular might have been included. However, I judged that they did not place enough graduates on the faculties of the other leading universities, particularly during the period 1945-1969, for inclusion. This list also aligns closely with contemporary reputational assessments, with ten of the eleven departments ranking in the top 11 in a 1964 poll (Allan Murray Carter, An Assessment of Quality in Graduate Education).
Also, Strassfeld notes (personal communication) that the list only includes Assistant, Associate, and full Professors, not instructors or lecturers (such as Marjorie Greene who was an instructor at Chicago in the 1940s).