The approach to critical realism, by D. Drake.--Pragmatism versus the pragmatist, by A. O. Lovejoy.--Critical realism and the possibility of knowledge, by J. B. Pratt.--The problem of error, by A. K. Rogers.--Three proofs of realism, by G. Santayana.--Knowledge and its categories, by R. W. Sellars.--On the nature of the datum, by C. A. Strong.