The function of reason is to dominate experience; and obviously openness to new impressions is no less necessary to that end than is the possession of principles by which new impressions may be interpreted. CHAPTER IX—HOW THOUGHT IS PRACTICAL [Sidenote: Functional relations of mind and body.] Nothing is more natural or more congruous with all the analogies of experience than that animals should feel and think. The relation of mind to body, of reason to nature, seems to be actually this: when bodies have reached a certain complexity and vital equilibrium, a sense begins to inhabit them which is focussed upon the preservation of that body and on its reproduction. This sense, as it becomes reflective and expressive of physical welfare, points more and more to its own persistence and harmony, and generates the Life of Reason. Nature is reason’s basis and theme; reason is nature’s consciousness; and, from the point of view of that consciousness when it has arisen, reason is also nature’s justification and goal. To separate things so closely bound together as are mind and body, reason and nature, is consequently a violent and artificial divorce, and a man of judgment will instinctively discredit any philosophy in which it is decreed. But to avoid divorce it is well first to avoid unnatural unions, and not to attribute to our two elements, which must be partners for life, relations repugnant to their respective natures and offices. Now the body is an instrument, the mind its function, the witness and reward of its operation. Mind is the body’s entelechy, a value which accrues to the body when it has reached a certain perfection, of which it would be a pity, so to speak, that it should remain unconscious; so that while the body feeds the mind the mind perfects the body, lifting it and all its natural relations and impulses into the moral world, into the sphere of interests and ideas.