To the physicist, pure and simple, the idea of a body facilitates the acquisition of a comprehensive survey in his department, and does not operate as a disturbance. So, also, the person that pursues purely practical ends, is materially assisted by the concept of the _I_ or Ego. For, unquestionably, every form of thought that has been voluntarily or involuntarily constructed for some especial purpose, possesses for that particular purpose a _permanent_ value. As soon, however, as physics and physiology touch, the ideas held in the one domain are discovered to be untenable in the other. From the striving after an adaptation of the one to the other arise the various atomic and monad theories—which are unsuccessful, however, in the attainment of their object. If we regard _sensations_, taken in the sense above defined, as _world-elements_ or elements of the All, the problems referred to are practically removed, and the _first_ and most important adaptation therefore effected. This basal notion (without any pretension to being a philosophy for all eternity) can at present be adhered to with respect to all provinces of experience; it is consequently the one that accommodates itself with the least expenditure, that is, more economically than any other, to the present _temporary state of collective science_. Moreover, in the consciousness of its purely economical office, this basal notion acts with most perfect tolerance. It does not obtrude itself into provinces in which the current conceptions are still adequate. It will ever be ready, upon subsequent extensions of the domain of experience, to give way to a better one. The philosophical point of view of the average man—if that term may be applied to the naïve realism of the ordinary individual—has a claim to the highest consideration. It has arisen in the progress of immeasurable time without the purposed assistance of man. It is a product of nature, and is preserved and sustained by nature. Everything that philosophy has accomplished—the _biological_ title of every advance, nay of every error, admitted—is, compared with _it_, but an insignificant and ephemeral product of art. And in reality, we see every thinker, every philosopher, the moment he is forced away from his one-sided intellectual occupation by some practical necessity, immediately fall back upon the universal point of view that all men hold in common. We seek by no means to discredit this point of view. The task that we have set ourselves is simply to show _why_ and to what _purpose_ for the greatest part of our life we occupy this point of view, and _why_ and for what _purpose_ we are provisorily obliged to abandon it. No point of view has an absolute _permanent_ validity. Each has an importance but for some one given end. ERNST MACH. THE ORIGIN OF MIND. #Given facts and deduced facts.#