XXXV. MR. SPENCER, THE ATHANASIAN CREED, AND THE ARTICLES 73 XXXVI. THE HUMOUR OF MATHEMATICIANS 74 XXXVII. THE PARADOXES OF LOGIC 75 XXXVIII. MODERN LOGIC AND SOME PHILOSOPHICAL ARGUMENTS 79 XXXIX. THE HIERARCHY OF JOKES 81 XL. THE EVIDENCE OF GEOMETRICAL PROPOSITIONS 83 XLI. ABSOLUTE AND RELATIVE POSITION 84 XLII. LAUGHTER 86 XLIII. "GEDANKENEXPERIMENTE" AND EVOLUTIONARY ETHICS 88 APPENDIXES 89 ABBREVIATIONS _A. A. W._ Lewis Carroll: _Alice's Adventures in Wonderland_, London, 1908. [This book was first published much earlier, but this was the edition used by Mr. R*ss*ll. The same applies to _H. S._ and _T. L. G._] _A. C. P._ John Henry Blunt (ed. by): _The Annotated Book of Common Prayer_, London, new edition, 1888. _A. d. L._ Ernst Schröder: _Vorlesungen über die Algebra der Logik, Leipzig_, vol. i., 1890; vol. ii. (two parts), 1891 and 1905; vol. iii.: _Algebra und Logik der Relative_, 1895. _E. N._ Richard Dedekind: _Essays on the Theory of Numbers_, Chicago and London, 1901. _E. L. L._ William Stanley Jevons: _Elementary Lessons in Logic, Deductive and Inductive. With copious Questions and Examples, and a Vocabulary of Logical Terms_, London, 24th ed., 1907 [first published in 1870]. _E. u. I._ Ernst Mach: _Erkenntnis und Irrtum: Skizzen zur Psychologie der Forschung_, Leipzig, 1906. _F. L._ Augustus De Morgan: _Formal Logic: or The Calculus of Inference, Necessary and Probable_, London, 1847. _Fm. L._ John Neville Keynes: _Studies and Exercises in Formal Logic_, 4th ed., London, 1906. _Gg._ Gottlob Frege: _Grundgesetze der Arithmetik begriffschriftlich abgeleitet_, Jena, vol. i., 1893; vol. ii., 1903. _Gl._ Gottlob Frege: _Die Grundlagen der Arithmetik: eine logisch-mathematische Untersuchung über den Begriff der Zahl_, Breslau, 1884. _G. u. E._ G. Heymans: _Die Gesetze und Elemente des wisenschaftlichen Denkens_, Leiden, vol. i., 1890; vol. ii., 1894. _H. J._ _The Hibbert Journal: a Quarterly Review of Religion, Theology and Philosophy_, London and New York. _H. S._ Lewis Carroll: _The Hunting of the Snark: an Agony in Eight Fits_, London, 1911. _M._ _The Monist: a Quarterly Magazine Devoted to Science and Philosophy_, Chicago and London. _Md._ _Mind: a Quarterly Review of Psychology and Philosophy_, London and New York.