6. THE LOGIC OF THE PSYCHOLOGICAL TERMS INVOLVED IN THE NOTION.
Concerning the knowing mind the psychologist classifies its activities and their products as follows:
| Activity | Product | ||||
| (1) | Presentative | ||||
| (1) | Sensation | Sensation | |||
| (2) | Perception | Percept | |||
| (2) | Representative | ||||
| (1) | Imagination |  | Image | ||
| (2) | Memory | ||||
| (3) | Thinking | ||||
| (1) | Conception | Concept | |||
| (2) | Judging | Judgment | |||
| (3) | Reasoning | Inference | |||
The notion as any product of the knowing mind includes the six products as indicated by the psychologist.
The individual notion which is intuitive includes the sensation, percept and image; the general notion which isa thought product stands for the concept, judgment and inference. To put it mathematically—
| Individual notion | = |  | sensation percept image | | = | intuitive products | | notion |
| General notion | = | | concept judgment inference | | = | thought products |
As we shall have occasion frequently to refer to these psychological terms it may be well to define them.
| Psychological Definition. | Logical Definition. |
| A sensation is the first and simplest mental result of the stimulation of an incarrying nerve. | A sensation is a vague, unlocalized mental product of the knowing mind. |
| A percept is a mental product which results from a consciousness of particular material things present to the sense. | A percept is a consciously localized group of sensations. |
| An image is a mental product which results from particular material things not present to the sense. | An image is a reproduced percept. |
| A concept is a representation in our minds answering to a general name. | A concept is a mental product arising from thinking many notions into one class. |
| A judgment is the result of asserting an agreement or disagreement between two ideas. | A judgment is the mental product arising from conjoining or disjoining notions. |
| An inference is a judgment derived from perceiving relations between other judgments. | An inference is a judgment derived from antecedent judgments. |
It is seen that the sensations furnish the raw material. Ignoring the few exceptions we may then say that a percept is a made-over group of sensations; a concept a thought-made group of percepts; a judgment a thought-made group of concepts; an inference a judgment derived from other judgments.
Developed thinking is first found in the concept, and as we study the thought products, “concept,” “judgment” and “inference,” the truth is forced upon us that thinking as a process aims to group the many into one.From many percepts is built the one concept, from two concepts is built the one judgment and from two judgments is built the one inference.[3]
Speaking figuratively, thinking is a matter of picking up the fragments along the shore of consciousness and tying them into bundles.