History of Ideas/History of Thought
As a student of the evolution of consciousness, Barfield is anxious to distinguish between three easily confused terms: (1) the history of ideas, (2) the history of thought, and (3) the history of thinking.

Working on the assumption that "throughout the course of history the many have accepted, as far as they were able, the thoughts which have been made for them by the few in the past, and the few have gone on constructing the opinion of the future" (HEW 114), Barfield sees the history of ideas--the sort of scholarly activity engaged in by individuals like the philosopher Arthur Owen Lovejoy, the historical reconstruction of a unit idea" (say, for example, the  philosophical tenet known as dualism), its origin, its dissemination, its mistaken notions,1 its modification, its demise--as only able to "collate conclusions." The history of ideas, Barfield argues, does not "attempt to penetrate into the very texture and activity of thought" (SA 90).

Moreover, the history of ideas, is grounded on a false assumption: "it assumes that all these philosophers were asking themselves the same questions and then finding different answers to them; that they were talking about the same things, and merely reasoning differently from them. That means that the history of philosophy is treated, in effect, as though it were a dialogue between contemporaries" (HGH 7-8).

The history of ideas readily falls prey as well to the worst kind of logomorphism. Indeed, Barfield contends, the history of ideas may owe its very existence as a method to the logomorphic bias of its time of origin.

[In the 19th Century] the development of human consciousness was . . . presented as a history of alpha-thinking beginning from zero and applied always to the same phenomena, at first in the form of erroneous beliefs about them and, as time went on, in the form of more and more correct and scientific beliefs. In short, the evolution of consciousness was reduced to a bare history of ideas. (SA 66)
Nor is a mere history of thought satisfactory for our needs. History of thought in Barfield's classification system is content with "observing that men began to think thus at a certain time,"2 while a "history of thinking," Barfield's preferred alternative, goes on to ask "how they became able to do so" (RCA 48). The latter goes on to the realization of the evolution of consciousness.

Methodologically convinced that "it is possible to fix a point in time, and then to cut a kind of cross-section, and define the exact, relation between language and thought at that particular moment" and that "this relation . . . is a fluid and flickering thing, varying incredibly in individual minds, leaping up and sinking down like a flame from one generation to another" (HEW 86), Barfield believes that "the progress of ideas has been as much, or more, a function of the evolution of consciousness than its vehicle. That is, of consciousness and its correlative, the phenomena or Collective Representations. . . . Accordingly, that evolution is much less dependent on contacts or communications than has generally been supposed" (SA 104).3

See in particular Saving the Appearances, passim, "History of Ideas: Evolution of Consciousness" (HGH 3-35).
1"No doubt the history of consciousness does include the story of any number of erroneous beliefs," Barfield notes in Saving the Appearances, "but the erroneous beliefs of human beings about phenomena are neither the most interesting nor the most important thing about the human beings or about the phenomena" (66-67).
2Elsewhere in Saving the Appearances, Barfield offers the following example of the unsatisfactory nature of the history of ideas, using his own terms, participation and alpha-thinking as test cases.
    Granted that for the past two or three thousand years the process of evolution has consisted in the gradual ousting of participation by alpha-thinking, is even the history of alpha-thinking itself just a history of thought in the ordinary sense, or can we also detect in it the subliminal working of an evolutionary process? A history of thought, as such, amounts to a dialectical or syllogistic process, the thoughts of one age arising discursively out of, challenging, and modifying the thoughts and discoveries of the previous one. Is this all we mean by the history of alpha-thinking? (67)
3The question remains of the role individual "great minds" play in the evolution of consciousness. In Saving the Appearances, Barfield offers the following tentative hypothesis.
    From the point of view of a history of consciousness, their writings [those of Plato and Aristotle, or any of the great philosophers] are rather landmarks to indicate the nature of that consciousness, inasmuch as they represent the human mind in its most wakeful state. At the same time, owing to the subtle link between thinking and figuration, and to the part played by language in evolving and sustaining the collective representations, they are by no means without causal significance. (97)