When the Ionian philosophers . . . asked what “all” was made of, or how “all” matter behaved, they were assuming a general notion, namely that of a parent substance, a final, universal matter to which all sorts of accidents could happen. This notion dictated the terms of their inquiries: what things were, and how they changed. Problems of right and wrong, of wealth and poverty, slavery and freedom, were beyond their scientific horizon. On these matters they undoubtedly adopted the wordless, unconscious attitudes dictated by social usage. The concepts that preoccupied them had no application in those realms, and therefore did not give rise to new, interesting, leading questions about social or moral affairs.  . . .
The limits of thought are not so much set from outside, by the fullness or poverty of experiences that meet the mind, as from within, by the power of conception, the wealth of formulative notions with which the mind meets experiences. Most new discoveries are suddenly-seen things that were always there. A new idea is a light that illuminates presences which simply had no form for us before the light fell on them. We turn the light here, there, and everywhere, and the limits of thought recede before it. A new science, a new art, or a young and vigorous system of philosophy, is generated by such a basic innovation. Such ideas as identity of matter and change of form, or as value, validity, virtue, or as outer world and inner consciousness, are not theories; they are the terms in which theories are conceived; they give rise to specific questions, and are articulated only in-the-form of these questions. Therefore one may call them generative ideas. the history of thought.
A tremendous philosophical vista opened when Thales, or perhaps one of his predecessors not known to us, asked: “What is the world made of?” For centuries men turned their eyes upon the changes of matter, the problem of growth and decay, the laws of transformation in nature. When the possibilities of that primitive science were exhausted, speculations deadlocked, and the many alternative answers were stored in every learned mind to its confusion, Socrates propounded his simple and disconcerting questions—not, “Which answer is true?” but: “What is Truth?” “What is Knowledge, and why do we want to acquire it?” His questions were disconcerting because they contained the new principle of explanation, the notion of value. Not to describe the motion and matter of a thing, but to see its purpose, is to understand it. From this conception a host of new inquiries were born. What is the highest good of man? Of the universe? What are the proper principles of art, education, government, medicine? 
Langer, Suzanne K. Philosophy in a New Key: A Study in the Symbolism of Reason, Rite, and Art (1941). New York: Mentor/American Library, 1951.
Last modified 14 July 2019