=6.= It is proper at this place to express dissent from some forms of theory which are at variance with the truth thus brought to light. Almost all of them are the outcome of the philosophical phenomenalism of which Kant's Critique of Pure Reason is the best illustration. It discredits the competency of our cognitive faculties to reach knowledge of things as they really are. We can know, it is said, only phenomena, while the noumena or things in themselves are incognizable; and doubt is raised whether there is a reality corresponding to what our faculties report. It is suggested that the data of these faculties, especially in the forms of intuition and universal judgments, may be mere "forms of thought," forms of knowing but not of real being, created within as well as by the mind itself, and projected thence in connection with apprehended phenomena. They may be mental fictions in whole or in part, in which the ideal must not be held as standing for actual being. Thus while time and space are necessary "forms of thought" under which all bodies and events must be known, yet time and space, it is alleged, may be but subjective forms given to the phenomena by and in the cognitive action. We are obliged, indeed, it is conceded, in practical life to follow the guidance of our necessary forms of thought. But the knowledge is merely regulative for present activity; and being a product created and shaped largely by the particular organization of our minds, this merely relative and regulative perception of truth may be different in other minds or be hereafter so changed as to present changed phenomena, superseding the judgments now given by other judgments under other views. When the adherents of the Positive Philosophy proceed to define matter as merely "a permanent possibility of sensations,"[21] faith in the reliability of our knowledge of the realities about us, as true for those realities, is thoroughly undermined. This tendency toward an invalidating of our knowledge as real for objective truth, has been fostered by recent physiological psychology which, under materialistic implications, magnifies the effect of the physical organization and condition upon the mental products. In these ways extreme idealism and positive materialism join hands in effort to reduce to uncertainty or illusion what our cognitive faculties perceive of reality and truth in both the material and moral systems about us. But ethical science, in harmony with the soundest and best sustained philosophy of the Christian centuries, rejects these agnostic suggestions, as not only unproved but untenable. They form a theory of our intellectual faculties which cuts away the foundations of all knowledge, even of that which is most clear, fixed, necessary and unchangeable in the intelligence of the race. The theory becomes intellectual suicide, as it nullifies the real validity of all the fundamental perceptions of both sense and reason, on which its own conclusion rests.