"Ethics could teach us only those purposes and ideals. If the teachers seeks insight into the means by which the aim can be reached, into the facts by which the child can be molded, his way must lead from ethics to psychology. Water flows downhill, anyhow, but to bring the water uphill hydraulic forces are indeed necessary. To overcome nature and instead to prepare for a life of ideals, to inhibit personal desires and instead to learn to serve the higher purposes indeed demands most serious and most systematic efforts. It is the teachers' task to make these efforts with all his best knowledge of mind and body, of social and of cultural values."

“The theorists of scientific management seem to think that the most subtle methods are indispensable for physical measurements, but for psychological inquiry nothing but a kind of intuition is necessary.”

“Our aim is to sketch the outlines of a new science which is to intermediate between the modern laboratory psychology and the problems of economics: the psychological experiment is systematically to be placed at the service of commerce and industry. So far we have only scattered beginnings of the new doctrine, only tentative efforts and disconnected attempts which have started, sometimes in economic, and sometimes in psychological, quarters. The time when an exact psychology of business life will be presented as a closed and perfected system lies very far distant. But the earlier the attention of wider circles is directed to its beginnings and to the importance and bearings of its tasks, the quicker and the more sound will be the development of this young science. What is most needed to-day at the beginning of the new movement are clear, concrete illustrations which demonstrate the possibilities of the new method. In the following pages, accordingly, it will be my aim to analyze the results of experiments which have actually been carried out, experiments belonging to many different spheres of economic life. But these detached experiments ought always at least to point to a connected whole; the single experiments will, therefore, always need a general discussion of the principles as a background. In the interest of such a wider perspective we may at first enter into some preparatory questions of theory. They may serve as an introduction which is to lead us to the actual economic life and the present achievements of experimental psychology”

“Only the subtle psychological individual analysis can overcome the superficial prejudices of group psychology.”

“WE have placed our psychotechnical interest at the service of economic tasks... The purpose before us was to find for every economic occupation the best-fitted personality, both in the interest of economic success and in the interest of personal development.”

“The inner labor, the inner values, and the inner difficulties and frictions are too often unknown to those who decide for a vocation, and they are unable to correlate those essential factors of the life-calling with all that nature by inheritance, and society by surroundings and training, have planted and developed in their minds.”

“The knowledge of nature and the mastery of nature have always belonged together.”