The John Locke Lectures (Wednesday - Week 6, TT19)

Phillip Pettit

The John Locke Lectures are among the world's most distinguished lecture series in philosophy. This list of past lecturers shows that most of the greatest philosophers of the last half century have been Locke Lecturers. The series began in 1950, funded from the generous bequest of Henry Wilde.

The Faculty acknowledges the generous support of these lectures by Oxford University Press and All Souls College.


Minds That Speak

The theme of the lectures is the constitutive dependence of our characteristic mental capacities on the ability to speak and the social life it makes possible. The claim defended is that speaking ensures that minded subjects have these capacities. The method followed is to explore, counterfactually, how the advent of even a simple, information-sharing language would elicit the capacities in subjects otherwise like us.

Minds that speak, so the argument goes, will more or less inevitably 1. decide about how to judge and what to think; 2. control their thinking by rule-based reasoning; 3. enjoy a special perceptual consciousness; 4. make commitments and form community; 5. constitute persons and selves; 6. assume responsibility for what they do; and, a topic for another occasion, 7. command one another’s respect. Is speech necessary for the capacities it is said to ensure? Perhaps not in the case of the first three, more purely psychological abilities; almost certainly, in the case of the other capacities, which have a social-psychological character.

Philip Pettit is the L.S. Rockefeller University Professor of Politics and Human Values at Princeton University, and Distinguished University Professor of Philosophy at the Australian National University, Canberra.


Abstract: Minds that speak assume responsibility for what they do 

Assume that I hold you responsible for acting (only) on judgments of value that we share. To hold you responsible for a particular failure, then—to blame you—must be to make two assumptions. First, that you have the general capacity to understand what it is to make judgments of value. And, second, that you had the capacity to act on our shared judgments of value in the case where you failed: that you could have done otherwise. Must minds that speak have the capacity to understand values? Yes. They will avow many desires, based on desiderata that make avowal sensible, both in an active manner and a virtual: that is, by failing to disavow desires that others manifestly expect them to act on. But they may often be unmoved by desires they previously avowed, while recognizing at the same time that it is a failure for them as commissive subjects not to stand by the avowed desires. And that should give them access to the idea of something’s being desirable in a familiar sense for any agent: it answers to desires that they may not feel but are committed to stand by. Must they also have the capacity to act on shared judgments of value associated with fitness for responsibility? Again, yes. In any functional society certain shared, routine norms of non-violence, non-fraudulence, and so on, are bound to materialize. Members will virtually avow the desirability of abiding by such norms, and virtually pledge to conform to them, insofar as they are manifestly expected both to judge conformity desirable and to intend to conform, and they acquiesce in that expectation. Registering that you have an important stake in proving faithful to those norms, then, I can exhort you to act appropriately, relying on your responsiveness to the considerations that triggered your commitment, including the reliance on others that it invited. I can say ‘you should and can tell the truth’, expecting this to help elicit the very responsiveness it posits: I can hold out the ideal in the expectation that it will move you, so that the ‘can’ does not just mark a (bare or robust) possibility. And if you fail to tell the truth, and I continue to think that you were (and are still) exhortable—whether by me, another or yourself—I will naturally express my impatience in words of a similar hortatory character: ‘you should and could have told the truth’.