抄録
It is well known that the phenomenal size of a thing is modified by its colour and brightness. In this article the phenomenon is studied chiefly in the consideration of the relation between the colours of the two fields, inner and outer, and between the brightness of these two, also. As our stimulus, we use two colour wheels, which has each a different size and is put one upon another. The observer's work is to inspect the size of the inner field, while the colour and brightness of the inner field or the outer were variously changed.
The results, which we have gained in the case, are summarized as follows:
1) The Phenomenal size of the inner field is :modified by the colour and brightness of the both fields and then the relation of these fields plays the most important part. It is possible to be said that the condition (the change of the colour or the brightness in the both field s) is effective not in colour (or brightness) itself, but in the change of the relation of them, in other words, in that of the structure of the visual field with their variation of the both fields. The inner field appears to be larger when the both fields seem homogeneous on the whole than when not so.
2) In the use of certain pair of colours and the same (or two different grades of brightness) the size of the inner field is conditioned by their positions, namely, inner or outer, or generally speaking by the spatial constellation of the visual field. Only by regarding to these conditions the conbination of colours and the spatial constellation of the visual field we are able to find a characteristic tendency of all colours (or of all grades of brightness) with respect to phenomenal size.
