Spelling irregularities where there was no obviously preferred version were left as is. Variants include: "alkalies" and "alkalis;" "apprise" and "apprize;" "coexistent" and "co-existent" (along with derivatives); "coextensive" and "co-extensive;" "e. g." and "e.g."; "encumbered" and "incumbered;" "formulæ" and "formulas;" "i. e." and "i.e."; "nonentity" and "non-entity;" "recal" and "recall" (and derivatives); "rectilinear" and "rectilineal;" "stopt" and "stopped."
Volume I. contains "το ὄν," while Volume II. spells it "τὸ ὄν." The spellings were left as is, in each case.
Changed "3" to "4" on page xiii: "4. —and from descriptions."
Inserted missing page number, "167," for Chapter VIII, section 7 on page xiii.
Moved the semi-colon inside the quotation marks in the footnote on page 14: "the Science of the Formal Laws of Thought;".
Changed "sub-divisions" to "subdivisions" on page 59: "three subdivisions."
Changed "pre-supposed" to "presupposed" on page 75: "they are presupposed."
In the footnote to page 122, changed the Greek character upsilon with dasia and oxia to upsilon with psili and oxia, making the transliteration "deuterai ousiai."
Changed "he" to "be" on page 189: "to which it may be reduced."
Changed "cb." to "ch." in footnote on page 227: "Theory of Reasoning, ch. iv."