Thought is not necessarily connected with a brain. It appears in the work of bees, of crystals, and throughout the purely physical world; and one can no more deny that it is really there, than that the colors, the shapes, etc., of objects are really there. Consistently adhere to that unwarrantable denial, and you will be driven to some form of idealistic nominalism akin to Fichte’s. Not only is thought in the organic world, but it develops there. But as there cannot be a General without Instances embodying it, so there cannot be thought without Signs. We must here give “Sign” a very wide sense, no doubt, but not too wide a sense to come within our definition. Admitting that connected Signs must have a Quasi-mind, it may further be declared that there can be no isolated sign. Moreover, signs require at least two Quasi-minds; a Quasi-utterer and a Quasi-interpreter; and although these two are at one (i.e., are one mind) in the sign itself, they must nevertheless be distinct. In the Sign they are, so to say, welded. Accordingly, it is not merely a fact of human Psychology, but a necessity of Logic, that every logical evolution of thought should be dialogic. You may say that all this is loose talk; and I admit that, as it stands, it has a large infusion of arbitrariness. It might be filled out with argument so as to remove the greater part of this fault; but in the first place, such an expansion would require a volume - and an uninviting one; and in the second place, what I have been saying is only to be applied to a slight determination of our system of diagrammatization, which it will only slightly affect; so that, should it be incorrect, the utmost certain effect will be a danger that our system may not represent every variety of non-human thought.
I almost despair of making clear what I mean by a “quasi-mind;” But I will try. A thought is not per se in any mind or quasi-mind. I mean this in the same sense as I might say that Right and Truth would remain what they are though they were not embodied, & though nothing were right or true. But a thought, to gain any active mode of being must be embodied in a Sign. A thought is a special variety of sign. All thinking is necessarily a sort of dialogue, an appeal from the momentary self to the better considered self of the immediate and of the general future. Now as every thinking requires a mind, so every sign even if external to all minds must be a determination of a quasi-mind. The quasi-mind is itself a sign, a determinable sign.
… quasi-mind is an object which from whatever standpoint it be examined, must evidently have, like anything else, its special qualities of susceptibility to determination.