[. . . . Phenomenalism is] the complex of sentiments and ideas that cluster around the tendency to interpret the phenomenal relations that are the object of science as a substantial order of things. . . . Once the symbols and relations of science are accepted as substances, the resulting phenomenal reality can be made the object of speculation as if it were a substantial reality; . . .

Into phenomenal reality, moreover, can be projected hopes and fears, and man can enter into experiential relations with it as if it were substantial reality; . . . [Man can act] on the basis of phenomenal speculation and under the influence of phenomenal obsessions. . . The complex of phenomenalism has never been isolated as a component factor in the intellectual and spiritual life of modern man, as far as we know, . . .