ABSTRACT
Whether one selects the year 1879, in which Wilhelm Wundt received a budget for what many people later considered the first laboratory of experimental psychology, or chooses 1860, the year of publication of Fechner’s Elements of Psychophysics, or pulls out still some other arbitrary date, such as the year 1875, when Wundt at Leipzig and James at Harvard each received space for a demonstration laboratory for psychology, clearly it was during the latter half of the 19th century that experimental psychology achieved its status as an independent science. The new discipline manifested the eight trends that are the focus of Part I: it was influenced by five developments in science (physiology and biology, quantification and atomism, and the founding of laboratories) and three in philosophy (associationism, critical empiricism, and scientific materialism).
