Disinterested and impartial inquiry is then far from meaning that knowing is self-enclosed and irresponsible. It means that there is no particular end set up in advance so as to shut in the activities of observation, forming of ideas, and application. Inquiry is emancipated. It is encouraged to attend to every fact that is relevant to defining the problem or need, and to follow up every suggestion that promises a clue. The barriers to free inquiry are so many and so solid that mankind is to be congratulated that the very act of investigation is capable of itself becoming a delightful and absorbing pursuit, capable of enlisting on its side man's sporting instincts. Just in the degree in which thought ceases to be held down to ends fixed by social custom, a social division of labor grows up. Investigation has become a dominant life occupation for some persons. Only superficially, however, does this confirm the idea that theory and knowledge are ends in themselves. They are, relatively speaking, ends in themselves for some persons. But these persons represent a social division of labor; and their specialization can be trusted only when such persons are in unobstructed co-operation with other social occupations, sensitive to others' problems and transmitting results to them for wider application in action. When this social relationship of persons particularly engaged in carrying on the enterprise of knowing is forgotten and the class becomes isolated, inquiry loses stimulus and purpose. It degenerates into sterile specialization, a kind of intellectual busy work carried on by socially absent-minded men. Details are heaped up in the name of science, and abstruse dialectical developments of systems occur. Then the occupation is "rationalized" under the lofty name of devotion to truth for its own sake. But when the path of true science is retaken these things are brushed aside and forgotten. They turn out to have been the toyings of vain and irresponsible men. The only guarantee of impartial, disinterested inquiry is the social sensitiveness of the inquirer to the needs and problems of those with whom he is associated.