Sixteen Experimental Investigations from the Harvard Psychological Laboratory by Hugo Münsterberg (100 books to read .txt) 📕

objective sensations which disturbs the judgment of distance, but the

sensation of inner origin which we set over against these outer

sensations. The piece of plush, because of the disagreeable sensations

which it gives, is judged shorter than the space filled with closely

crowded tacks. Dresslar seems to have overlooked entirely the fact

that the feelings and emotions can be sources of illusions in the

amount of movement, and hence in our judgments of space. The

importance of this element has been pointed out by Münsterberg[19] in

his studies of movement.

[18] Delabarre, E.B., ‘Ueber Bewegungsempfindungen,’ Inaug.

Dissert., Freiburg, 1891.

[19] Münsterberg, H., ‘Beiträge zur Experimentellen Psychol.,’

Freiburg i. B., 1892, Heft 4.

Dresslar says again, “The explanations heretofore given, wholly based

on the differences in the time the eye uses in passing over the two

spaces, must stop short of the real truth.” My experiments, however,

as I have already indicated, go to prove quite the contrary. In short,

I do not think we have any means of distinguishing our tactual

judgments of time from our similar judgments of space. When the

subject is asked to measure off equal spaces, he certainly uses time

as means, because when he is asked to measure off equal times he

registers precisely the same illusion that he makes in his judgments

of spatial distances. The fact that objectively equal times were used

by Dresslar in his experiments is no reason for supposing that the

subject also regarded these times as equal. What I have here asserted

of active touch is true also of the resting skin. When a stylus is

drawn over the skin, the subject’s answer to the question, How long is

the distance? is subject to precisely the same illusion as his answer

to the question, How long is the time?

I can by a simple illustration show more plainly what I mean by the

statement that the blending of the inner and outer sensations is

necessary for the perception of space. I shall use the sense of sight

for the illustration, although precisely the same reasoning would

apply to the sense of touch. Suppose that I sat in an entirely passive

position and gazed at a spot on an otherwise blank piece of paper

before me. I am perfectly passive so far as motion on my part is

concerned. I may be engaged in any manner of speculation or be in the

midst of the so-called active attention to the spot; but I must be and

for the present remain motionless. Now, while I am in this condition

of passivity, suppose the spot be made to move slowly to one side by

some force external to myself. I am immovable all the while, and yet

am conscious of this movement of the spot from the first position,

which I call A, to the new position, A’, where it stops. The

sensation which I now have is qualitatively different from the

sensation which I had from the spot in its original position. My world

of experience thus far has been a purely qualitative one. I might go

on to eternity having experiences of the same kind, and never dream of

space, or geometry, nor should I have the unique experience of a

geometrical illusion, either optical or tactual. Now suppose I set up

the bodily movements of the eyes or the head, or of the whole body,

which are necessary to follow the path of that point, until I overtake

it and once more restore the quality of the original sensation. This

circle, completed by the two processes of external activity and

restoration by internal activity, forms a group of sensations which

constitutes the ultimate atom in our spatial experience. I have my

first spatial experience when I have the thrill of satisfaction that

comes from overtaking again, by means of my own inner activity, a

sensation that has escaped me through an activity not my own. A being

incapable of motion, in a world of flux, would not have the spatial

experience that we have. A being incapable of motion could not make

the distinction between an outer change that can be corrected by an

internal change, and an outer change that cannot so be restored. Such

an external change incapable of restoration by internal activity we

should have if the spot on the paper changed by a chemical process

from black to red.

Now such a space theory is plainly not to be confused with the theory

that makes the reversibility of the spatial series its primary

property. It is evident that we can have a series of sensations which

may be reversed and yet not give the notion of space. But we should

always have space-perception if one half of the circular process above

described comes from an outer activity, and the other half from an

inner activity. This way of describing the reversibility of the

spatial series makes it less possible to urge against it the

objections that Stumpf[20] has formulated against Bain’s genetic

space-theory. Stumpf’s famous criticism applies not only to Bain, but

also to the other English empiricists and to Wundt. Bain says: “When

with the hand we grasp something moving and move with it, we have a

sensation of one unchanged contact and pressure, and the sensation is

imbedded in a movement. This is one experience. When we move the hand

over a fixed surface, we have with the feelings of movement a

succession of feelings of touch; if the surface is a variable one,

the sensations are constantly changing, so that we can be under no

mistake as to our passing through a series of tactual impressions.

This is another experience, and differs from the first not in the

sense of power, but in the tactile accompaniment. The difference,

however, is of vital importance. In the one case, we have an object

moving and measuring time and continuous, in the other case we have

coëxistence in space. The coëxistence is still further made apparent

by our reversing the movement, and thereby meeting the tactile series

in the inverse order. Moreover, the serial order is unchanged by the

rapidity of our movements.”[21]

[20] Stumpf, K., ‘Ueber d. psycholog. Ursprung d.

Raumvorstellung,’ Leipzig, 1873, S. 54.

[21] Bain, A., ‘The Senses and the Intellect,’ 3d ed., New

York, 1886, p. 183.

Stumpf maintained in his exhaustive criticism of this theory, first,

that there are cases where all of the elements which Bain requires for

the perception of space are present, and yet we have no presentation

of space. Secondly, there are cases where not all of these elements

are present, and where we have nevertheless space presentation. It is

the first objection that concerns me here. Stumpf gives as an example,

under his first objection, the singing of a series of tones, C, G, E,

F. We have here the muscle sensations from the larynx, and the series

of the tone-sensations which are, Stumpf claims, reversed when the

muscle-sensations are reversed, etc. According to Stumpf, these are

all the elements that are required by Bain, and yet we have no

perception of space thereby. Henri[22] has pointed out two objections

to Stumpf’s criticism of Bain’s theory. He says that Bain assumes,

what Stumpf does not recognize, that the muscle sensations must

contain three elements—resistance, time, and velocity—before they

can lead to space perceptions. These three elements are not to be

found in the muscle sensations of the larynx as we find them in the

sensations that come from the eye or arm muscles. In addition to this,

Henri claims that Bain’s theory demands a still further condition. If

we wish to touch two objects, A and B, with the same member, we

can get a spatial experience from the process only if we insert

between the touching of A and the touching of B a continual

series of tactual sensations. In Stumpf’s instance of the singing of

tones, this has been overlooked. We can go from the tone C to the tone

F without inserting between the two a continuous series of musical

sensations.

[22] Henri, V., ‘Ueber d. Raumwahrnehmungen d. Tastsinnes,’

Berlin, 1898, S. 190.

I think that all such objections to the genetic space theories are

avoided by formulating a theory in the manner in which I have just

stated. When one says that there must be an outer activity producing a

displacement of sensation, and then an inner activity retaining that

sensation, it is plain that the singing of a series of tones ascending

and then descending would not be a case in point.

*

TACTUAL TIME ESTIMATION.

BY KNIGHT DUNLAP.

I. GENERAL NATURE OF THE WORK.

The experiments comprised in this investigation were made during the

year 1900-1901 and the early part of the year 1901-1902. They were

planned as the beginning of an attempt at the analysis of the

estimation of time intervals defined by tactual stimulations. The only

published work in this quarter of the field so far is that of

Vierordt,[1] who investigated only the constant error of time

judgment, using both auditory and tactual stimulations, and that of

Meumann,[2] who in his last published contribution to the literature

of the time sense gives the results of his experiments with ‘filled’

and ‘empty’ tactual intervals. The stimuli employed by Meumann were,

however, not purely tactual, but electrical.

[1] Vierordt: ‘Der Zeitsinn,’ Tübingen, 1868.

[2] Meumann, E.: ‘Beiträge zur Psychologie des

Zeitbewusstseins,’ III., Phil. Studien, XII., S. 195-204.

The limitation of time intervals by tactual stimulations offers,

however, a rich field of variations, which promise assistance in the

analytical problem of the psychology of time. The variations may be

those of locality, area, intensity, rigidity, form, consecutiveness,

and so on, in addition to the old comparisons of filled and empty

intervals, intervals of varying length, and intervals separated by a

pause and those not so separated.

To begin with, we have selected the conditions which are mechanically

the simplest, namely, the comparison of two empty time intervals, both

given objectively with no pause between them. We have employed the

most easily accessible dermal areas, namely, that of the fingers of

one or both hands, and introduced the mechanically simplest

variations, namely, in locality stimulated and intensity of

stimulation.

It was known from the results of nearly all who have studied the time

sense experimentally, that there is in general a constant error of

over-or underestimation of time intervals of moderate length, and

from the results of Meumann,[3] that variations in intensity of

limiting stimulation influenced the estimation decidedly, but

apparently according to no exact law. The problem first at hand was

then to see if variations introduced in tactual stimulations produce

any regularity of effect, and if they throw any new light on the

phenomena of the constant error.

[3] Meumaun, E.: ‘Beiträge zur Psychologie des Zeitsinns,’ II.,

Phil. Studien, IX., S. 264.

The stimulations employed were light blows from the cork tip of a

hammer actuated by an electric current. These instruments, of which

there were two, exactly alike in construction, were similar in

principle to the acoustical hammers employed by Estel and Mehner. Each

consisted essentially of a lever about ten inches in length, pivoted

near one extremity, and having fastened to it near the pivot an

armature so acted upon by an electromagnet as to depress the lever

during the passage of an electric current. The lever was returned to

its original position by a spring as soon as the current through the

electromagnet ceased. A clamp at the farther extremity held a small

wooden rod with a cork tip, at right angles to the pivot, and the

depression of the lever brought this tip into contact