(474) 
chophysical law? As we know, the mathematical formulation of the 
latter is the following: 
B pag Re Geet ek 
in which p and s represent constants, R the stimulus and Z the 
effect. The curve expressed by (8) is a logarithmic curve showing 
great resemblance to the curve representing our law, but, unlike 
ours, possessing no asymptote. This fact is one reason amongst 
others why the psychophysical cannot express the relation between 
stimulus and effect for single neura or for the muscle (myophysical 
law). In psychophysics, where it is never allowed to make use of 
stimuli, capable of damaging the sense-organ, scarcely ever an effect 
is reached that may be considered a maximum, consequently the 
possibility of examining the upper part of the curve is excluded. 
As far however as my law may be represented with sufficient 
accuracy by a lineal function of the 2nd degree (because we are not 
allowed to introduce more than three constants), so far it is found 
to be in perfect accordance with the psychophysical law, as this 
latter too may be represented in the same manner by expanding in 
a series. 
And I wish to point out the fact that this part is relatively 
a rather large one: for a height of curve reaching more than one 
half of the maximum, we might with sufficient accuracy for practical 
aims, make use of a lineal function with three constants or of the 
law of WeBeR-FECHNER. 
In all experiments that have hitherto been taken to confirm or 
to combat the law of WersER-FECHNER, generally not even approxi- 
mately so large a part of the curve has been examined. 
Now does there exist no single fact, capable of procuring us a 
decisive answer on the question whether for the sense-perception the 
possibility or the certainty of a maximal sensation may be taken 
for granted; a fact capable of deciding whether or not a psycho- 
physical curve possesses an asymptote? I believe such a fact to 
exist for one sense-perception, viz. for the sense of weight. For. 
the asymptote may be said to have been reached at the point 
where the action of the muscle proves insufficient to lift a burden: 
at that moment we have the maximum sensation of weight 
that may be obtained with the organism employed, and that 
cannot be any more surpassed. Probably therefore for the sense 
of weight there exists an asymptote, approached by the curve expres- 
