1. Applied Psychology
Munsterberg's aim in writing this book is to interpret some of the findings of "the psychological experiment" to commerce and industry. In his time, psychology was a new doctrine (EN: The book was published in 1913), psychology was a new doctrine, consisting of "tentative efforts and disconnected attempts" that seemed to have merit, but was not very well developed or organized, and the time when the psychology of commercial life would be perfected "lies very far distant" and in many instances psychology seemed stuff and nonsense that is thoroughly detached from practical concerns - and further, that the psychologists themselves are very reluctant to correlate their observations and theories with practical life.
Moreover, psychology remained largely philosophical and theoretical, and was merely the bauble of idle minds until about 50 years prior when the practitioners began to correlate their ideas to any observable evidence. It was only about 30 years prior that psychologists moved into the laboratory, and only about 10 years prior that any systematic attempt was made to apply the experimental results of psychology to the needs of society.
The same is true of many of the sciences, as it was not very long ago that chemistry departed from the realm of detached ideas and mysticism (the notion that material objects were made of earth, wind, fire, and water and obeyed an otherworldly mandate) - and significant progress was made when science at long last descended to earth. Consider the amazing benefits rendered to mankind when electricity was studied systematically rather than speculated about with an almost religious sense of awe and wonder.
(EN: This calls to mind that there is definitely a middle stage between philosophy and science that consists almost entirely of quackery. Consider the ludicrous employment of electricity for specious health benefits, sometimes by half-wits acting in earnest upon a smidgeon of scientific evidence. I despair that remains to this day the state of psychology in the commercial world - it remains vaguely understood, but much is pronounced to be certain and true based on scant and specious evidence.)
He speaks briefly of the reluctance of science to apply itself to practical concerns, which is often perceived as a sort of arrogant detachment or a fearfulness that one's claims will be disproven in practical application. But this reluctance is also quite justified when science is "forced into the rush of day" when the investigation is ongoing and the early results are supported by scant evidence.
Laymen are quick to perceive that science has offered incontrovertible evidence when the scientists have merely noted an apparent connection between cause and effect and have not yet sufficiently investigated its veracity and there remains great uncertainty. Laymen are also quick to ignore the conditions under which a scientific finding holds true, presuming a result achieved under exacting laboratory conditions will bear out in entirely different conditions. And when the consequence of their folly is failure, laymen are eager to lay the blame at the feet of science, dismissing the intellectual rather than admitting their own foolishness and lack of understanding. Is it any wonder that the scientist is disdainful of the half-witted "practical men" who behave in this manner?
As a young science, psychology remains extremely tentative and speculative - and as a natural science, it has the peculiar problem of the idiosyncratic nature of the human mind. A chemist can be certain of the contents of a beaker because the substances within are refined to a high degree of purity, but where does there exist a pure mind, or even a typical one? Human beings have a broad range of experiences, attitudes, capacities, and talents and cannot be reduced to their elements in the same manner. There is nothing that can be said to be common to all human beings, only generalizations about masses.
This does not make psychology fruitless, but it is and will likely ever remain to be a very imprecise science as a result. In actual life we never deal with uniform human beings, and cannot predict with perfect certainty the reaction a given person may have as people can react quite differently to similar stimuli in similar situations. Men may be skilled or hapless, intelligent or stupid, sensitive or obtuse, quick or slow, brave or fearful, energetic or inert, and possessing by degrees hundreds of other qualities.
So in taking action in the world of such idiosyncratic men, we must acknowledge that there is an element of unpredictability and as such take action not with absolute certainty, but with reasonable expectations of a desired outcome. And for the present, at least, we must accept that psychology is imperfect, but is likely the best that can be had.
(EN: In terms of the half-wittedness of laymen, the rejection of something imperfect for the sake of something even less perfect is also a common tendency. In terms of psychology, the reaction to its uncertainty is leveraged as an excuse to return to blindly groping and acting on gut feel, which is to reject an approach that is imperfect and to cling to something that is far more flawed.)
Even though psychology is still a young field, significant progress has been made in recent decades, and while it is still far from perfection it does seem at times to at least be serviceable enough - and as such the considerations that follow in this book are likely imperfect, but we're better off using than abandoning them, with the knowledge that they will be refined, and that their failure in application does not nullify scientific theories buy merely identify opportunities for refinement.