Plan of the Work
354. Section 1. One, Two, Three. Already written.
Section 2. The triad in reasoning. Not touched. It is to be made as follows. 1. Three kinds of signs; as best shown in my last paper in the Am. Jour. Math.2) 2. Term, proposition, and argument, mentioned in my paper on a new list of categories.3) 3. Three kinds of argument, deduction, induction, hypothesis, as shown in my paper in Studies in Logic.4) Also three figures of syllogism, as shown there and in my paper on the Classification of Arguments.5) 4. Three kinds of terms, absolute, relative, and conjugative, as shown in my first paper on Logic of Relatives.6) There are various other triads which may be alluded to. The dual divisions of logic result from a false way of looking at things absolutely. Thus, besides affirmative and negative, there are really probable enunciations, which are intermediate. So besides universal and particular there are all sorts of propositions of numerical quantity. For example, the particular proposition: Some A is B, means »At least one A is B.« But we can also say: At least 2 A's are B's. Also, All the A's but one are B's, etc., etc., ad infinitum. We pass from dual quantity, or a system of quantity such as that of Boolian algebra, where there are only two values, to plural quantity.
Section 3. The triad in metaphysics. This chapter, one of the best, is to treat of the theory of cognition.
Section 4. The triad in psychology. The greater part is written.
Section 5. The triad in physiology. The greater part is written.
Section 6. The triad in biology. This is to show the true nature of the Darwinian hypothesis.
Section 7. The triad in physics. The germinal section. 1. The necessity of a natural history of the laws of nature, so that we may get some notion of what to expect. 2. The logical postulate for explanation forbids the assumption of any absolute. That is, it calls for the introduction of Thirdness. 3. Metaphysics is an imitation of geometry; and mathematicians having declared against axioms, the metaphysical axioms are destined to fall too. 4. Absolute chance. 5. The universality of the principle of habit. 6. The whole theory stated. 7. Consequences.
Section 8. The triad in sociology or, shall I say, pneumatology. That the consciousness is a sort of public spirit among the nerve-cells. Man as a community of cells; compound animals and composite plants; society; nature. Feeling implied in Firstness.
Section 9. The triad in theology. Faith requires us to be materialists without flinching.1)