tivistic maxim that, "no hypothesis is admissible which is not capable of verification by direct observation.")
3. "On a New List of Categories," pp. 287-298. The categories are: Being, Quality (Reference to a Ground), Relation (Reference to a Correlate), Representation (Reference to an Interpretant), Substance. "Logic has for its subject-genus all symbols and not merely concepts." Symbols include terms, propositions, and arguments.
4. "Upon the Logic of Mathematics," pp. 402-412. "There are certain general propositions from which the truths of mathematics follow syllogistically."
5. "Upon Logical Comprehension and Extension," pp. 416-432. (Interesting historical references to the use of these terms and an attack on the supposed rule as to their inverse proportionality.)
B. "Description of a Notation for the Logic of Relations," in
Memoires of the American Academy, Vol. 9 (1870), pp.
317-378. (Shows the relation of inclusion between classes
to be more fundamental than Boole's use of equality. Extends
the Booleian calculus to DeMorgan's logic of relative
terms.)
C. "On the Algebra of Logic," American Journal of Mathematics, Vol. 3 (1880), pp. 15-57. (Referred to by Schroeder as Peirce's Hauptwerk in "Vorlesungen über die Algebra der Logik," Vol. 1., p. 107.)
D. "On the Logic of Number," American Journal of Mathematics, Vol. 4 (1881), pp. 85-95.
E. "Brief Description of the Algebra of Relatives," Reprinted from ??, pp. 1-6.
F. "On the Algebra of Logic: A Contribution to the Philosophy of Notation," American Journal of Mathematics, Vol 7 (1884), pp. 180-202.
G. "A Theory of Probable Inference" and notes "On a Limited Universe of Marks" and on the "Logic of Relatives" in "Studies in Logic by members of the Johns Hopkins University," Boston, 1883, pp. 126-203.
H. "The Regenerated Logic," Monist, Vol. 7, pp. 19-40.
"The Logic of Relatives," Monist, Vol. 7, pp. 161-217. (An
elaborate development of his own logic of relatives, by way
of review of Schroeder's book.)
I. Miscellaneous Notes, etc.
1. Review of Venn's "Logic of Chance," North American Review, July, 1867.
2. "On the Application of Logical Analysis to Multiple Al-
