Renouvier and Fouillée were neo-Kantians who saw indeterminism and determinism as antinomies needing to be reconciled. Both speculated about free will somehow based on indeterminism, but Peirce has relatively little to say about the will. He is boastful about his knowledge of early philosophers, and so we can presume he was familiar with the objection to chance as the cause of human actions for which we can claim human responsibility. So Peirce may have been guarded that chance could a basis for free will, and he talks vaguely about two sides to the question and a reductio ad absurdum.

Peirce's life work was primarily in science, and he was well aware that observational error made the doctrine of necessity strictly unprovable by any experiment. It was the work of astronomers that had led to the theory of observational errors, which became the normal distribution law in the calculus of probabilities. Peirce used the theory of errors in his thirty years of scientific work for the U.S. Coast Survey, and his father had developed an important criterion for rejecting observational data when it was too far from the standard deviation of errors. For Peirce necessity and determinism were merely assumptions. There is nothing necessary and logically true of the universe, he learned from discussions of Alexander Bain in his Metaphysical Club.

Peirce modeled his thinking on the work of Charles Darwin, but he was not satisfied with Darwin's fortuitous variation and natural selection. He falsely associated it with the Social Darwinist thinking of his time and called it a "greed philosophy." Peirce also rejected the deterministic evolution scheme of Herbert Spencer, and proposed his own grand scheme for the evolution of everything including the laws of Nature! He called this synechism, a coined term for continuity, in clear contrast to the merely random events of his tychism. Pierce's evolutionist thinking resembles Hegel. It was the basis for the evolutionary growth of variety, of irregular departures from an otherwise mechanical universe, including life and Peirce's own original thoughts. For Peirce and Hegel, ideas are living things with meanings that grow over time. Peirce was a "realist" in that he believed these ideas have a metaphysically real existence.

There is no doubt that language evolves, and Peirce made foundational contributions to the theory of semiotics, the study of signs and symbols.

Like Hegel, Peirce arranged his arguments in triads, often with Hegel's thesis-antithesis-synthesis structure. Thus Peircean evolution has three levels, the Darwinian (random and indeterminate), the Spencerian (mechanical and determinate), and Peirce's synechism (union of the two first levels). >p/> Peirce's conception of thought also has random, determined, and continuous levels.

From The Monist, vol. 3, pp 176-200 (1893), CPP, vol VI, p.190.

I propose to devote a few pages to a very slight examination of these questions in their relation to the historical development of human thought. I first formulate for the reader's convenience the briefest possible definitions of the three conceivable modes of development of thought, distinguishing also two varieties of anancasm and three of agapasm.

The tychastic development of thought, then, will consist in slight departures from habitual ideas in different directions indifferently, quite purposeless and quite unconstrained whether by outward circumstances or by force of logic, these new departures being followed by unforeseen results which tend to fix some of them as habits more than others.

The anancastic development of thought will consist of new ideas adopted without foreseeing whither they tend, but having a character determined by causes either external to the mind, such as changed circumstances of life, or internal to the mind as logical developments of ideas already accepted, such as generalizations.

The agapastic development of thought is the adoption of certain mental tendencies, not altogether heedlessly, as in tychasm, nor quite blindly by the mere force of circumstances or of logic, as in anancasm, but by an immediate attraction for the idea itself, whose nature is divined before the mind possesses it, by the power of sympathy, that is, by virtue of the continuity of mind; and this mental tendency may be of three varieties, as follows. First, it may affect a whole people or community in its collective personality, and be thence communicated to such individuals as are in powerfully sympathetic connection with the collective people, although they may be intellectually incapable of attaining the idea by their private understandings or even perhaps of consciously apprehending it. Second, it may affect a private person directly, yet so that he is only enabled to apprehend the idea, or to appreciate its attractiveness, by virtue of his sympathy with his neighbors, under the influence of a striking experience or development of thought. The conversion of St. Paul may be taken as an example of what is meant. Third, it may affect an individual, independently of his human affections, by virtue of an attraction it exercises upon his mind, even before he has comprehended it. This is the phenomenon which has been well called the divination of genius; for it is due to the continuity between the man's mind and the Most High.

[T]he question of free-will and fate in its simplest form, stripped of verbiage, is something like this: I have done something of which I am ashamed; could I, by an effort of the will, have resisted the temptation, and done otherwise? The philosophical reply is, that this is not a question of fact, but only of the arrangement of facts. Arranging them so as to exhibit what is particularly pertinent to my question -- namely, that I ought to blame myself for having done wrong -- it is perfectly true to say that, if I had willed to do otherwise than I did, I should have done otherwise. On the other hand, arranging the facts so as to exhibit another important consideration, it is equally true that, when a temptation has once been allowed to work, it will, if it has a certain force, produce its effect, let me struggle how I may. There is no objection to a contradiction in what would result from a false supposition. The reductio ad absurdum consists in showing that contradictory results would follow from a hypothesis which is consequently judged to be false. Many questions are involved in the free-will discussion, and I am far from desiring to say that both sides are equally right. On the contrary, I am of opinion that one side denies important facts, and that the other does not. But what I do say is, that the above single question was the origin of the whole doubt; that, had it not been for this question, the controversy would never have arisen; and that this question is perfectly solved in the manner which I have indicated.

The Fixation of Belief Popular Science Monthly, vol.12, 1-15. (November 1877)

How To Make Our Ideas Clear Popular Science Monthly, vol.12, 286-302. (January 1878)

The Order of Nature Popular Science Monthly, vol.13, 203-217. (June 1878)

The Architecture of Theories from Monist, vol.1, p.161-176, (1891)

The Doctrine of Necessity Examined from Monist, vol.2 (1892)