Heliogravure by H. F. Juette, public domain
Ernst Waldfried Josef Wenzel Mach was born on 18 February 1838 in Chrlice, near Brno, currently in the Czech Republic. While Mach was a talented child, he had difficulties with classical languages, and his initial schooling was not trouble free. He began his schooling at the age of nine at a gymnasium, but he did not complete the curriculum. Mach received his education at home from his parents up to the age of 14. He was then enrolled at a piaristic school in Kroměříž. In 1855, he entered the University of Vienna to study mathematics, physics, and philosophy, and in 1860, received a doctorate in Physics. Upon completion of his inaugural dissertation (habilitation), he worked at the University of Vienna as a private associate professor.
In 1864, he accepted a position as Professor of Mathematics at the University of Graz and lectured on mathematics, physics, physiology, and psychology. During the years 1867–1895, he was professor of experimental physics at the Charles University in Prague. In 1879, he became the rector of the Charles University for one year. Mach met with Palacky and Purkyně during his stay in Prague and among other things became interested in visual and auditory perception and examined the air shock waves caused by fast-flying projectiles. His stay in Prague was, however, influenced by growing nationalism and anti-Semitism (Mach had many Jewish friends). Thus in 1895, he returned to Vienna and worked as professor of inductive philosophy.
In 1889, Mach endured a cardiac arrest that led to the paralysis of the upper part of his body. Nonetheless, he continued to propose experiments and publish his work. Ernst Mach died on 19 February 1916 in Vaterstetten, Germany.
Mach was interested in chemistry, physiology, and psychology and was a skilled experimenter. In addition to exact sciences, such as physics and mathematics, Mach was also interested in psychology and strived to unify these disciplines. He attempted to help establish psychophysics as a new discipline to determine the relationship between physical stimuli and sensations. He assumed it necessary to build upon psychology according to physical models in order to be able to develop psychophysics and explain the relationships between stimuli and percepts. This was in line with Gustav Fechner’s efforts who was leading this endeavor at that time.
It should be borne in mind that nearly the entire focus of the empirical psychology in the nineteenth century was on perception, and mainly on visual and auditory aspects of perception. Relevant experimental psychology involved using specific coils or discs, which were compared against percepts of individuals. Mach’s contribution in the field was most profound in the exploration of the physiology of visual perception. One of his experiments became later known as Mach’s band effect. Nonetheless, Mach, even in his sixties, was not content on only indulging in experimental work. From a philosophical standpoint, he believed in the duality of the physical and the psychological and that they share a parallel course. He argued, however, that both sides of reality have their ontological basis in one perceived reality. This view corresponded with Mach’s phenomenonalistic focus.
Mach’s major contribution to science, however, was perhaps in the field of physics. He contributed to the overall paradigm shift in accepted hypotheses of his time. The most important work that best characterizes Mach’s opinions in this field can be found in his book “Die Mechanik in ihrer Entwicklung” which was first published in 1883 [1]. In this book, he criticized the concept of Newtonian physics due to his view that it was unfruitful and outside the borders of perception. Mach also rejected atomic theory and considered it a product of theoretical physics. According to Mach, the atom was a conception for something that could not be defined by sensations and complicated the explanation of many phenomena. This work is considered a turning point in the evolution of physics in the nineteenth century. The most cited passages concern the criticism of Newtonian physics and classical mechanics. Mach criticized several sections of Newtonian physics based on the idea that a phenomenon should correspond to sensations (everything that is immediately accessible to us). In Newton’s system, only reasoning based on direct observation of psychical reality was possible and justified, e.g., from observed collision between two objects forces could be assumed as physical variables allowing to predict the result of that collision. This opinion in the context of the representative epistemology was widely respected. For Mach, the sole basis of scientific research was based on sensations, and thus Newtonian reasoning of reality was seen as an embezzlement of proclaimed empirical foundations of science. For Mach’s phenomenalism, judgments of objective physical reality were unjustified, metaphysical and did not belong to science.
Based on these views, Mach criticized a wide range of classical physical concepts such as force, causality, mass and most importantly absolute values, i.e., absolute space, time and movement. In Mach‘s concept, these were mere metaphysical constructs and unjustified extensions of empirical relationships outside the bounds of empiricism. Mach declaimed not only Newtonian absolutes, but also all absolute quantities of contemporary science such as the absolute thermal zero point or the absolute speed of light. He considered theoretical physics unfruitful, which went baselessly beyond the borders of experience. Against such physics he then placed physics based only on experience, i.e., in the context of his teachings describing the sensations, and mathematical description of their relationship. Mach remained opposed to theoretical physics throughout his life. From the beginning of the twentieth century, Mach’s work was criticized by several scientists including those that were influenced by his work such as Einstein and Planck [2].
45.1 Mach Band Effect
Examples of the Mach Band Effect
The relationship between distance from edge and brightness of stimuli