ABSTRACT
. . . When I wrote my article I was sure that it was impossible to discover atomic propositions by actual analysis. Of this I am now very doubtful, and I cannot therefore be sure that they may not be discovered to be all of one or other of a series of forms which can be expressed by R1 (x), R2 (x, y) R3 (x, y z), etc. in which case we could, as Mr Russell has suggested, define individuals as terms which can occur in propositions oí any of these forms, universals as terms which can only occur in one form. This I admit may be found to be the case, but as no one can as yet be certain what sort of atomic propositions there are, it cannot be positively asserted; and there is no strong presumption in its favour, for I think that the argument of my article establishes that nothing of the sort can be known a priori.
