We will convene a series of three interlinked workshops in Paris focused on a parallel development within the Anglo-American philosophical tradition and its French counterpart. The development in question pertains to the philosophical theorization of the concepts of expression and mutual acknowledgement and their pertinence to addressing what is known in the analytic tradition as “the problem of other minds” and in the phenomenological tradition as “the problem of the Other.” In each of these traditions, drawing on the work principally of Ludwig Wittgenstein, J. L. Austin, Elizabeth Anscombe, and Stanley Cavell, an alternative to the original analytical and phenomenological approaches has recently emerged. Its central idea is that the logically fundamental case of being known to each other is not to be conceived as a pair of separate but reciprocal acts of two agents, but as an act for two. This act for two is what Stanley Cavell calls mutual acknowledgement. This recent and sudden parallel development within French and Anglo-American philosophy is not only in itself striking, but also brings to the fore how these two putatively mutually opposed traditions have until now shared a deeply entrenched set of philosophical assumptions.