semblance of reality was lent to the hypothesis of the atomic structure
of matter. Something similar has occurred in the field of optics. Here,
after having been forced to recognize the fallacy of Newton's theory,
the spectator's mind has been driven to form a concept of the nature of
light which is further than ever from the truth. For what then remains
of light is - in Eddington's words - a 'quite irregular disturbance,
with no tendency to periodicity', which means that to light is assigned
the quality of an undefined chaos (in the negative sense of this word)
sprung from pure chance.

Moreover, as Eddington shows, the question whether the optical
contrivance 'sorts out' from the chaotic light a particular
periodicity, or whether it 'impresses' this on the light, becomes just
'a matter of expression'.11 So here, too, the modern investigator is
driven to a resigned acknowledgment of the principle of Indeterminacy.

No such conclusions are forced upon the one who studies the spectrum
phenomenon with the eyes of Goethe. Like the modern experimenter, he,
too, is faced with the question 'Discovery or Manufacture?' and he,
too, finds the answer to be 'Manufacture'. But to him nature can
disclose herself as the real manufacturer, showing him how she goes to
work in bringing about the colours, because in following Goethe he is
careful to arrange his observations in such a way that they do not veil
nature's deeds.

1 'To see is my dower, to look my employ.' Words of the Tower-Watcher
in Faust, II, 5, through which Goethe echoes his own relation to the
world.

2 The last chapter but two in the edition of 1924.