|Geach, Peter T.
Books on Amazon
Facts / Geach: 19. century, like syphilis - wrong attempt to reduce hypothetical statements to categorical statements - e.g. the fact of the thunder now and the fact of the lightning after.
Conjunction / sentence / Frege: "p u q" is a phrase that is different from "p" and "q" individually - Mill: ditto: otherwise "a group of horses" would be "a kind of horse" - but not: e.g. "Jim is convinced and his wife is unfaithful "- solution:" the fact that ... "is always to split as a pair of statements.
Logic Matters Oxford 1972