Bauhaus-Universität Weimar

Experimental Psychology: A Manual of Laboratory Practice, Vol. II: Quantitative Experiments, part 2: Instructor's Manual
Titchener, Edward B.
The Metric Methods 
ungsber. d. kais. Akad. d. Wiss. zu Wien, math.-naturw. Cl., vi., 
Abth. i., 340). As applied to the determination of the DL, this 
method of disappearing differences requires that two sensibly 
different R be presented to O, and the one gradually increased 
(or diminished) until the original difference becomes un- 
Is there, now, any way of combining these two methods, with 
elimination of constant and variable errors, for the determination 
of a DL in Midler’s sense? Fechner recommends the averaging 
of the ascending and descending j. n. d. This procedure gives us 
a value which is greater than our own DL, but which has psycho¬ 
logical validity: the average value is a Fechnerian DL freed from 
certain errors. To average j. n. d. and positive equality (on the 
analogy of Lichtenfels’ combined method) is quite another mat¬ 
ter. Is it psychologically justifiable? And, if justifiable, is it 
psychologically valuable ? 
Lichtenfels, we note, did not do it ; he left his two series side 
by side. Judged from the standpoint of Midler’s DL, he was 
right. The average of j. n. d. (ascending) and of positive 
equality (descending) will yield a value smaller than our DL, as 
Fechner’s method yields a value that is larger.1 Nevertheless, 
the two partial methods can be combined. The suggestion comes 
from Delbceuf. “ On fait d’abord croître la différence d,” says 
Delbœuf in 1873, “jusqu’à ce qu’elle devient perceptible; puis 
on la fait décroître jusqu’à ce qu’elle cesse de l’être.” 2 The de¬ 
scending series extends, not to positive equality, but only to lapse 
of difference. Müller, in 1878, works out this idea of Delbœuf's 
in his own method of ‘least differences’ (G., 63 f.),—the first 
instance of methodical combination of j. n. d. with j. not-n. d. in 
order to the determination of a true DL by minimal changes.3 
According to Müller’s method, we set out from a clearly supra¬ 
liminal difference of r and rv and diminish r1 uniformly and very 
1 We assume, for purposes of the argument, that judgments of ‘positive equal¬ 
ity ’ are possible. See Müller, M., 12 f. 
2 Éléments, 9. Müller (G., 66 f., n.) is mistaken in identifying this suggestion 
with that of Fechner. 
3Lipps, Massmethoden, 51 f. (Arch., 203 f.). Lipps evidently underestimates 
the complexity of the problem which the history of the method presents : cf. 57, 72 
(Arch., 209, 224).


Sehr geehrte Benutzer,

aufgrund der aktuellen Entwicklungen in der Webtechnologie, die im Goobi viewer verwendet wird, unterstützt die Software den von Ihnen verwendeten Browser nicht mehr.

Bitte benutzen Sie einen der folgenden Browser, um diese Seite korrekt darstellen zu können.

Vielen Dank für Ihr Verständnis.