[This posting is referred to at the end of the remarks under "Otagai" (Hoji 2006) in the Downloadable Papers page.]

Popper 1983: p. xx (i.e., the 20th page of "Introduction 1982," HH) contains (i).

(i) But when is a statement falsifiable? It is of great importance to current discussion to notice that falsifiability in the sense of my demarcation criterion is a purely logical affair. It has to do only with the logical structure of statements and of classes of statements. And it has nothing to do with the question whether or not certain possible experimental results would be accepted as falsifications.

Popper, K. 1983. Realism and the Aim of Science: From the Postscript to the Logic of Scientific Discovery, Routledge, New York.