514.

[3] Thiéry, A.: _Philos. Studien_, 1896, Bd. XII., S. 121.

[4] Dresslar, F.B.: _Amer. Journ. of Psy._, 1894, Vol. VI., p.
332.

At the beginning of the present investigation, the preponderance of
testimony was found to be in favor of the view that filled space is
underestimated by the skin; and this view is invariably accompanied by
the conclusion, which seems quite properly to follow from it, that the
skin and the eye do not function alike in our perception of space. I
began my work, however, in the belief that there was lurking somewhere
in the earlier experiments a radical error or oversight. I may say
here, parenthetically, that I see no reason why experimental
psychologists should so often be reluctant to admit that they begin
certain investigations with preconceptions in favor of the theory
which they ultimately defend by the results of their experiments. The
conclusions of a critical research are in no wise vitiated because
those conclusions were the working hypotheses with which the
investigator entered upon his inquiry. I say frankly, therefore, that
although my experiments developed many surprises as they advanced, I
began them in the belief that the optical illusions are not reversed
for touch. The uniformity of the law of sense perception is prejudiced
if two senses, when affected by the same objective conditions, should
report to consciousness diametrically opposite interpretations of
these same objective facts. I may say at once, in advance of the
evidence upon which I base the assertion, that the belief with which I
began the experiments has been crystallized into a firm conviction,
namely, that neither the illusion for open or filled spaces, nor any