We are part of the Universe, our senses have been evolved in and by it; it follows that they are harmonious with it, and that the way it appeals to our senses is a true way; though their obvious limitation entitles us to expect from time to time fresh discoveries of surprising and fundamental novelty, and a growing perception of tracts beyond our ancient ken. Some critics there are, however, who, calling themselves scientific, have made up their minds in a negative direction and a contrary sense. These are impressed not only with the _genuineness_ of the truth afforded us through our senses and perceptions, but with its _completeness_; they appear to think that the main lines of research have already been mapped out or laid down, they will not believe that regions other than those to which they are accustomed can be open to scientific exploration; especially they imagine that in the so-called religious domain there can be no guides except preconception and prejudice. Accordingly, they appear to disbelieve that anyone can be conscientiously taking trouble to grope his way by patient inquiry, with the aid of such clues as are available; and in order to contradict the results of such inquiry they fall into the habit of doing that of which they accuse the workers,--they appeal to sentiment and presumption. They talk freely about what they believe, what they think unlikely, and what is impossible. They are governed by prejudice; their minds are made up. Doubtless they regard knowledge on certain topics as inaccessible, so they are positive and selfsatisfied and opinionated and quite sure. They pride themselves on their hard-headed scepticism and robust common sense; while the truth is that they have bound themselves into a narrow cell by walls of sentiment, and have thus excluded whole regions of human experience from their purview. * * * * * It so happens that I have been engaged for over forty years in mathematical and physical science, and for more than half that period in exploration into unusual psychical development, as opportunity arose; and I have thus been led to certain tentative conclusions respecting permissible ways of regarding the universe. First, I have learned to regard the universe as a concrete and full-bodied reality, with parts accessible and intelligible to us, all of it capable of being understood and investigated by the human mind, not as an abstraction or dream-like entity whose appearances are deceptive. Our senses do not deceive us; their testimony is true as far as it goes. I have learned to believe in Intelligibility.