ASSOCIATION OF IDEAS
Having formed general ideas, or Concepts, it is important that we associate them with other general ideas. In order to fully _understand_ a general idea we must know its associations and relations. The greater the known associations or relations of an idea, the greater is our degree of understanding of that idea. If we simply know many thousands of separated general ideas, without also knowing their associations and relations, we are in almost as difficult a position as if we merely knew thousands of individual percepts without being able to classify them in general concepts. It is necessary to develop the faculty of associating ideas into groups, according to their relations, just as we group particular ideas in classes. The difference, however, is that these group-ideas do not form classes of a genus, but depend solely upon associations of several kinds, as we shall see in a moment.
Halleck says: “All ideas have certain definite associations with other ideas, and they come up in groups. There is always an association between our ideas, although there are cases when we cannot trace it…. Even when we find no association between our ideas, we may be sure that it exists…. An idea, then, never appears in consciousness unless there is a definite reason why this idea should appear in preference to others.” Brooks says: “One idea or feeling in the mind calls up some other idea or feeling with which it is in some way related. Our ideas seem, as it were, to be tied together by the invisible thread of association, so that as one comes out of unconsciousness, it draws another with it. Thoughts seem to exist somewhat in clusters like the grapes of a bunch, so that in bringing out one, we bring the entire cluster with it. The law of association is thus the tie, the thread, the golden link by which our thoughts are united in an act of reproduction.”
The majority of writers confine their consideration of Association of Ideas to its relation to Memory. It is true that the Laws of Association play an important part in Memory Culture, but Association of Ideas also form an important part of the general subject of Thought-Culture, and especially in the phase of the latter devoted to the development of the Understanding. The best authorities agree upon this idea and state it positively. Ribot says: “The most fundamental law which regulates psychological phenomena is the Law of Association. In its comprehensive character it is comparable to the law of attraction in the physical world.” Mill says: “That which the law of gravitation is to astronomy, that which the elementary properties of the tissues are to physiology, the Law of Association of Ideas is to psychology.”
There are two general principles, or laws, operative in the processes of Association of Ideas, known as (1) Association by Contiguity; and (2) Association by Similarity, respectively.
Association by Contiguity manifests particularly in the processes of memory. In its two phases of (1) Contiguity of Time; and (2) Contiguity of Space, respectively, it brings together before the field of consciousness ideas associated with each by reason of their time or space relations. Thus, if we remember a certain thing, we find it easy to remember things which occurred immediately before, or immediately after that particular thing. Verbal memory depends largely upon the contiguity of time, as for instance, our ability to repeat a poem, or passage from a book, if we can recall the first words thereof. Children often possess this form of memory to a surprising degree; and adults with only a limited degree of understanding may repeat freely long extracts from speeches they have heard, or even arbitrary jumbles of words. Visual memory depends largely upon contiguity of space, as for instance our ability to recall the details of scenes, when starting from a given point. In both of these forms of association by contiguity the mental operation is akin to that of unwinding a ball of yarn, the ideas, thus associated in the sequence of time or place, following each other into the field of consciousness. Association by Contiguity, while important in itself, properly belongs to the general subject of Memory, and as we have considered it in the volume of this series devoted to the last mentioned subject, we shall not speak of it further here.
Association by Similarity, however, possesses a special interest to students of the particular subject of the culture of the Understanding. If we were compelled to rely upon the association of contiguity for our understanding of things, we would understand a thing merely in its relations to that which went before or came after it; or by the things which were near it in space–we would have to unwind the mental ball of time and space relations in order to bring into consciousness the associated relations of anything. The Association of Similarity, however, remedies this defect, and gives us a higher and broader association. Speaking of Association of Similarity, Kay says: “It is of the utmost importance to us in forming a judgment of things, or in determining upon a particular line of conduct, to be able to bring together before the mind a number of instances of a _similar_ kind, recent or long past, which may aid us in coming to a right determination. Thus, we may judge of the nature or quality of an article, and obtain light and leading in regard to any subject that may be before us. In this way we arrange and classify and reason by induction. _This is known as rational or philosophical association._”
Halleck says: “An eminent philosopher has said that man is completely at the mercy of the association of his ideas. Every new object is seen in the light of its associated ideas…. It is not the business of the psychologist to state what power the association of ideas _ought_ to have. It is for him to ascertain what power it _does_ have. When we think of the bigotry of past ages, of the stake for the martyr and the stoning of witches, we can realize the force of Prof. Ziehen’s statement: ‘We cannot think as we _will_, but we _must_ think as just those associations which happen to be present prescribe.’ While this is not literally true, it may serve to emphasize a deflecting factor which is usually underestimated.”