Although Hermann von Helmholtz was one of most remarkable figures of nineteenth-century science, he is little known outside his native Germany. Helmholtz (1821-1894) made significant contributions to the study of vision and perception and was also influential in the painting, music, and literature of the time; one of his major works analyzed tone in music. This book, the first in English to describe Helmholtz's life and work in detail, describes his scientific studies, analyzes them in the context of the science and philosophy of the period-in particular the German Naturphilosophie-and gauges his influence on today's neuroscience.

Helmholtz, trained by Johannes Muller, one of the best physiologists of his time, used a resolutely materialistic and empirical scientific method in his research. This puts him in the tradition of Kant and the English empirical philosophers and directly opposed to the idealists and naturalists who interpreted nature based on metaphysical presuppositions. Helmholtz's research on color vision put him at odds with Goethe's more romantic theorizing on the subject; but at the end of his life, Helmholtz honored Goethe's contributions, acknowledging that artistic intuition could reveal truths about the human mind that are inaccessible to science.

Helmholtz's work, eclipsed at the beginning of the twentieth century by new ideas in neurophysiology, has recently been rediscovered. We can now recognize in Helmholtz's methods-which were based on his belief in the interconnectedness of physiology and psychology-the origins of neurosciencetic intuition could reveal truths about the human mind that are inaccessible to science.