Rationality (1964), Jonathan Bennett’s first book, was published when he was thirty-four years old, and it exhibits the intensity of a young philosopher who is quite sure he sees a way to cut through a forest of dubious, ideology-ridden, squishy philosophy of mind and set a few things straight. Since the terrain he was scouting and clarifying was the same terrain that I was then embarking on, with similar ambitions, I read his book when it first came out through the dust and smoke of my own earliest efforts to conquer these topics. The result, I confess, was that I simultaneously misread, underestimated, and covertly absorbed much of what he was on about and then proceeded to reinvent some of his wheels in my own work without realizing it until years later...I was not the only explorer of this territory who chose to find other paths to Bennett’s destination, but here we all are, and a review of his book may consolidate the gains.--Daniel Dennett, (2016) Jonathan Bennett's Rationality in Ten Neglected Classics of Philosophy [ed. E. Schliesser], 256.
Dennett graciously and generously admits here, with the benefit of a half century's worth of hindsight, that he did not fully grasp the content ("misread") and significance ("underestimated") of a work written by a contemporary who shared, in many ways, his intellectual outlook. Bennett went on to have a distinguished career, both as a philosophical historian and philosopher of language as well as as a metaphysician. At Syracuse he helped nourish and steer the revival of analytical metaphysics (less noticed because it does not fall easily in Kripke-Lewis centered narratives we tell ourselves). While this is not a tragic story of gross injustice, it's fair to say that Dennet's reaction to Rationality is not unique; the little book, while not ignored (it has about 250 citations in google.scholar) did not have a huge, recognized impact on the profession. (The impact of Dennett's own Content and Consciousness, which appeared half decade later, is a useful contrast.) This despite the fact that the book is written in accessible, lively language; it appeared in paperback in a then "unduly prestigious series of books" (Dennett, 257), and it avoids unexplained jargon. It also anticipates, as Dennett notes throughout his piece, quite a few insights later developed by others.
The failure of impact is especially notable because Bennett announces, as Dennett notes in his article, that he is doing something significant (and as Dennett notes, original): he describes the work as “extremely ambitious conceptual inquiry”? on p. 1 of Rationality. Before I get to the significance (and further characterization) of the phenomenon that this is an instance of, Dennett offers a few useful suggestions on the lack of impact. For example, the series in which Rationality appeared was associated with ordinary language philosophy, already in decline by the mid 1960s (258). (Dennett also indicts ordinary language philosophy for its comical lack of ambition--a judgment worth reconsidering some time.) By contrast, Bennett's kind of conceptual analysis was more ambitious (and Dennett recognizes that in a sense Bennett is trying to displace Kant's synthetic a priori.) Dennett notes in passing that, "Philosophers get largely ignored by Bennett, aside from brief passing acknowledgments of Kant, Wittgenstein, Descartes, Locke, Hume, and Popper, but it is clear that he is deliberately avoiding tussles with a host of contemporary philosophers, indirectly criticizing their positions." (261) So one may suspect that other philosophers ignored Bennett because he ignored them and was, then, not in a position to get away with it.
One could read Dennett as implying (it's not his main point in context) that part of the problem for Bennett is not sociological, but philosophical:
Here I think the main strength of Bennett’s method is also its weakness. As a piece of conceptual analysis it is hard to fault the claim that conventionality presupposes reasons had by reasoners, but this blinds him to the prospect of an intermediate position which is not readily articulated without a helping of initially counterintuitive innovation— a “move” that I have only recently perfected (to my satisfaction): drawing a quite sharp distinction between doing things for reasons and having reasons for doing things. There are reasons aplenty in nature (I call them free- floating rationales): trees do things for reasons, fungi do things for reasons...but they do not (usually) have reasons for doing these things. (262)
My interest here is not Dennett's philosophical point (important as it is! -- the distinction between doing things for reasons and having reasons for doing things will be very useful in the (philosophy of) social science(s) because it will remove the stranglehold of methodological individualism and renew interest in a species of functional explanation). The point is rather that even if one grants that Bennett missed a step, everybody else did too.
There is, however, a more subtle version of the point in Dennett: "By not quite nailing the distinction between there being reasons and an agent’s having reasons, Bennett misses the intermediate cases that naturalism requires, in order to account for the gradual emergence of function by the march of evolution and by the development of the individual." (264) This suggests a more historical explanation of the lack of uptake for Bennett: he is not easily slotted into the rising wave of philosophical naturalism (associated with Quine and, of course, Dennett). There is something to this point; the non-naturalists that gained distinction (e.g., Nagel, Searle) situated themselves against it. That gave them a place as the opposition. Bennett is much harder to slot into simplifying narratives teachers tell their students. (He was not obscure in the period, because Dennet himself includes Bennett in his "Mid-Term Examination" included in the Intentional Stance, and in that piece Dennett had explicitly recognized the "parallel paths" (348) between himself and Bennett, and their lack of mutual citation (349, where Davidson is included.))
A central theme of Dennett's chapter is that he is not alone in having missed Bennett's point (even when they directly confronted each other's views in print), and he calls attention to the fact that Quine, Millikan, and the Pittsburgh school all did so, too. While there is some self-interest in not fully crediting another with one's own insights, it remains remarkable that such excellent peers missed the point. This is significant because both epistemologists and contextual historians of philosophy put great faith in the discern-ability of such peers. But the fact is, as is recognized in principle, but often not in practice, is that their judgment is fallible. The market in ideas is imperfect, after all. That is to say, sometimes not being a peer or an outsider or being later in time allows one to see with greater clarity (than previously) what is at stake than an active participant. It is an obvious point, but it is dis-allowed by those that privilege peers in epistemology and historical context in history (of philosophy). This is why (a) in epistemology we should also find a place to canvass non-peers, and (b) in history of philosophy make space for anachronism to ensure historical accuracy.
I encouraged Dennett to write about Bennett because I was curious what he would say. For, (a) I had noticed that Dennett (who is one of my undergraduate teachers) notes Rationality in passing in the Intentional Stance; I did so only after (b) I had been a course assistant in a class by Bill Wimsatt on "Philosophy of Mind and Science Fiction" in the mid-90s at Chicago. Wimsatt, a contemporary of Bennett and Dennett, trained at Pittsburgh (and represents the naturalistic wing also associated with the Churchlands), who is primarily known as a philosopher of biology. Wimsatt assigned Rationality and taught it with gusto to his undergraduates. Wimsatt also taught Dennett (in his philosophy of biology graduate seminar), but (to the best of my fragile memory) did not compare Bennett with Dennett.
Somebody eager to defend the judgments of peers may suggest that Wimsatt ought to count as a peer. I fully grant the point. But while it's true that Wimsatt grasped some of the significance of Rationality he did not (I think) really use Bennett in his own work and so his judgment is not reflected in the profession's conversation. This points the way toward a distinction between formal (public) and informal (private) peer judgments, but about that some other time.