There is a large variety of means whereby man’s mind and body carry out their uses. A number of them are under some conscious direction, as is the flow of thought into speech. Others are more fully automatic, such as happens with the co-ordination of sight, hearing and general muscular activity when driving a car. It is noteworthy that the human organism tends to use all the means it has for carrying out its uses as economically as possible; thus consciously learned functions tend to become habitual so as to free more energy for consciously dictated functions. For the sake of being useful, man’s mind needs to be as free as possible of those functions which are routine in the protection and maintenance of the whole organism. Central Nervous System centers automatically direct the program of protection and maintenance by activating and inactivating various bodily systems. Except for the process of filling the stomach, for example, digestion automatically takes place through Central Nervous System control. Similarly ordered is blood circulation, and the distribution of the products of digestion to where they are needed.
Several manuscripts in Swedenborg’s handwriting, formerly regarded as Swedenborg’s own productions and so listed in Hyde’s Bibliography (1906), have since been found to have originated with Christopher Polhem. Thus the text in Mathematics (Hyde XXIII) referred to in Swedenborg’s letter of February 14, 1716, was printed in part at Upsala in 1716, anonymously except for the phrase, “delivered by C. P.” Swedenborg probably had revised the treatise. An incomplete draft of the whole proposed book was found among Polhem’s manuscripts.