(see also Tychism, Agapasm )

"It is that synthesis of tychism and of pragmatism for which I long ago proposed the name, Synechism." ('Recent Developments of Existential Graphs and their Consequences for Logic', CP 4.584, 1906)

      " [Synechism is] that tendency of philosophical thought which insists upon the idea of continuity as of prime importance in philosophy and, in particular, upon the necessity of hypotheses involving true continuity." ('Dictionary of Philosophy and Psychology' vol. 2, CP 6.169, 1902)

"... the characteristic of my doctrine, namely, that I chiefly insist upon continuity, or Thirdness, and, in order to secure to thirdness its really commanding function, I find it indispensable fully [to] recognize that it is a third, and that Firstness, or chance, and Secondness, or Brute reaction, are other elements, without the independence of which Thirdness would not have anything upon which to operate. Accordingly, I like to call my theory Synechism, because it rests on the study of continuity." (Cambridge Lectures on Reasoning and the Logic of Things, CP 6.202, 1898)

      "The word synechism is the English form of the Greek {synechismos}, from {synechés}, continuous. For two centuries we have been affixing -ist and -ism to words, in order to note sects which exalt the importance of those elements which the stem-words signify. Thus, materialism is the doctrine that matter is everything, idealism the doctrine that ideas are everything, dualism the philosophy which splits everything in two. In like manner, I have proposed to make synechism mean the tendency to regard everything as continuous.
[---] I carry the doctrine so far as to maintain that continuity governs the whole domain of experience in every element of it." ('Immortality in the Light of Synechism', EP 2:1, 1893)

      "There is a famous saying of Parmenides {esti gar einai, méden d' ouk einai}, "being is, and not-being is nothing." This sounds plausible; yet synechism flatly denies it, declaring that being is a matter of more or less, so as to merge insensibly into nothing. [---]
      Synechism, even in its less stalwart forms, can never abide dualism, properly so called. [---] In particular, the synechist will not admit that physical and psychical phenomena are entirely distinct, -- whether as belonging to different categories of substance, or as entirely separate sides of one shield, -- but will insist that all phenomena are of one character, though some are more mental and spontaneous, others more material and regular. [---]
      Nor must any synechist say, "I am altogether myself, and not at all you.
      Synechism refuses to believe that when death comes, even the carnal consciousness ceases quickly." ('Immortality in the Light of Synechism', EP 2:2-3, 1893)

"... The tendency to regard continuity, in the sense in which I shall define it, as an idea of prime importance in philosophy may conveniently be termed synechism. [---] I attempted, a good many years ago, to develop this doctrine in the Journal of Speculative Philosophy (Vol. II); but I am able now to improve upon that exposition, in which I was a little blinded by nominalistic prepossessions." ('The Law of Mind', CP 6.103, 1892)

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Abbreviations (CP, EP, etc.) and sources; see here