systematic philosophy of the time, even as its source—the deeply religious turn of Fechner's nature had little place among the conventional philosophizing motives.
Incidentally it may be said that the publication of Fechner of a little volume of riddles in rhythm for children between the appearance of the "Zend Avesta" and the work on the plant soul may throw some light on the failure of the professorial absolute idealist to understand the nature of the versatile founder of the "Philosophie von Unten."
But the year 1848 was a very unfavorable one in Germany for the reception of a new philosophy, particularly for a philosophy to which it was so tempting to attach the tag of mysticism. The German folk, wearied with the pretensions and dialectics of the rationalistic philosophers, aroused by vital questions of constitutional government and interested in the vigorous growth of natural science, had no time to waste on such questions as the mentality of plants and planets; the shallow materialism of Vogt and Büchner seemed to fall in easily with current theories of physical science; as a verbal proposition it seemed much easier to understand the statement that the brain secretes thought as the liver secretes bile, than to work out Fechner's involved, if keen, reason in regard to the seat of the soul. And so the "Zend Avesta" rested quietly with the "Nana" on the book shelves of the publishers. But in no wise discouraged, Fechner once more attacked the question of the parallelism of soul and body as a special problem "von unten auf," and in 1859 published the famous treatise on psychophysics.
The motive for this work was to determine, if possible, exact relations existing between the mental acts, the "psyche," and the accompanying physical process, or, in short, to determine quantitative relations existing between mind and body. Considering the general disbelief in regard to the possibility of such determinations, which had been summed up by Kant in the dictum that psychology could never become a science because it could never be treated mathematically, Fechner's plan might reasonably be termed bold. But when one thinks of the practical difficulties of the undertaking that Fechner had to create new scientific concepts and name them, that he had to create and develop totally new methods of investigation and that he had to invent new apparatus or apply old to totally new uses, it might seem as if Fechner had passed from the region of the improbable to that of the impossible.
The occasion for the psychophysics was a simple investigation on our discriminative sensibility for lines and weights, made by the physiologist E. H. Weber, one of the "seven sages of Göttingen." Weber simply states that we have the power to distinguish between the lengths of two lines which are to each other as 39 to 40 and between weights with a ratio of 20 to 30. Moreover, these ratios are general, holding for centi-
