A psychologist cuts out a lobe of my brain (nihil animale a me alienum puto) and then, when I find I cannot express myself, he says, "You see, your faculty of language was localized in that lobe." No doubt it was; and so, if he had filched my inkstand, I should not have been able to continue my discussion until I had got another. Yea, the very thoughts would not come to me. So my faculty of discussion is equally localized in my inkstand. It is localization in a sense in which an object may be in two places at once." CP 7.366, 1907And in 1902, he maintained that it is "more accurate to say that there are stores of knowledge in a library than to say that there are books there which, if I was reading, having become acquainted with the languages they are printed in, would be conveying knowledge to my mind" (Charles Sanders Peirce, Collected Papers,, Volume II, Elements of Logic, p. 2.55f).
I don't know whether that means he believed in a kind of active externalism a la Chalmer and Clark or whether he simply thought that it is a mistake to "localize" knowledge at all. If he claimed the latter, he must have conceived of it as virtual, and as being neither neither in the mind nor in space. I suspect, however, he did not mean externalism. In any case, in November 30, 1868, he wrote to W. T. Harris that the mind as a whole is "virtual" and cannot really exist at any particular moment in time. Perhaps he is making a similar point about knowledge. It does not simply consist of "states of mind," but it is not truly external either. "inner" and "outer" make little sense when applied to parts of a network.
And what does all this have to do with note-taking? Well it seems to mean to me that your note-taking system also constitutes such a virtual system that consists of interactions between you (or your mind) and your notes. This virtual system is not subject to the same limitations as the "unaided mind" mind would be. Comparing the mind to a machine, he argues in 1887 (Logical Machines), "the mind working with pencil and plenty of paper has no such limitation. It presses on and on, and whatever limits can be assigned to its capacity today, may be overstepped tomorrow" (Writings of Charles S. Peirce: A Chronological Edition, Volume 6, p. 71). He thinks that algebra is a prime example of this. I would argue that, insofar as Peirce is correct, it would apply to other pursuits as well.
1. For active externalism or the extended mind thesis, see here.