The John Locke Lectures (Wednesday - Week 4, 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 form commitments and community

In our discussion of the capacities of judgment, reasoning and consciousness, we have been focused on the personal psychological impact of speech. In the remaining lectures, we shift the focus to the social psychological impact of speech, as we might describe it. The first effect, explored here, is to make such minds capable of mutual commitment: capable of speaking with authority for themselves in communicating with others. Minds that speak can rely on a maker’s knowledge of their attitudes to set aside misleading-mind excuses—‘I misread my thoughts’— and thereby avow (rather than just report) various attitudes. And they can rely on that knowledge to set aside changed-mind excuses also—‘I changed my view’—in pledging (rather than just avowing or reporting) their intentions. In such exercises, they make their words more expensive and credible than they would otherwise be and, in that game-theory sense, make commitments to one another. As a result of that capacity for commitment, they can form distinctive kinds of community. They can build up common ground with one another—say, a set of beliefs to which each is manifestly committed—in any conversation. They can readily form joint intentions, positioning themselves to be able to avow an intention on behalf of a collectivity. And they can constitute themselves as a group agent, with each being manifestly committed to acting by established protocols when they act for the group as a whole; and this, across any in a range of possible scenarios.