I have been describing the ordinary and principal form of the concrete type. It consists in the immediate and spontaneous substitution of a particular case (fact or individual) for the general term. In certain observations a slightly different _variation_ may be detected; I have encountered it among several historians and learned men. In the ordinary type, the whole (general) is thought by means of the part (concrete); in the variation, the thinking is by analogy, and the mechanism seems to be reduced to pure association. A few examples will explain the distinction. The replies in duplicate were given by different persons. _Number_: the “Language of Calculation,” Pythagoras. _Cause_: Hume’s theory of causality; Kant’s theory. _Law_: the “Tables of Malaga,” Montesquieu’s definition. _Color_: the chemistry of the spectrum. _Justice_: Littré’s definition. _Animal_: the πὲρι ψυχῆς of Aristotle. _Time_: a vague metaphysical theory. _Relation_: discussion of Ampère and Tracy on this subject. _Infinity_: books on mathematics. _Color_: treatises of photography, etc. It might be objected that there is a certain association in ordinary cases as in these; but the distinction will readily be perceived. The former proceed from that which contains, to the content—from the class to the fact: they think the whole by means of the part; there is an internal association. The latter form associations beside and from without. Apparently these do not reach to the concrete, they stop half way; for a complete generality they substitute a semi-generality. Further than this, my data are neither sufficiently numerous, nor clear enough, for the point to be insisted on. 2. VISUAL TYPOGRAPHIC TYPE. Nothing is easier to define. In its pure form it consists in seeing printed words and nothing more; in three cases words were seen _written_. Among some the vision of the printed words was accompanied by a concrete image as in the first type, but only for semi-concrete concepts (dog, animal, color); for the higher abstracts (time, cause, infinity, etc.) the typographical vision alone exists.[82] This mode of representation is widely distributed among those who have read much; but there are many exceptions. No doubt many of my readers will discover from self-observation that they belong to this type. I have further noticed that all who have this mode of representation regard it as normal, and necessary, in anyone who knows how to read. This is a fallacy. I do not possess it myself in the faintest degree, and have met many others who resemble me. Thus I was little prepared to discover this type; and had even reached my thirtieth observation without suspecting it, when I encountered such a clear case as to put me on the track. I was interrogating a well-known physiologist. To every word except _Law_ and _Form_, he replied “I see them in printed characters” and was able to describe these accurately.