The Soul, or Rational Psychology

It seems clearly evident that this work is the conclusion and peak of the great series titled the Animal Kingdom original: Regnum Animale; Swedenborg used this term to mean "The Kingdom of the Soul," referring to the human body as the soul's domain. This is apparent from how the contents align with the subjects mentioned in the final sections of the author’s planned outline for his work. It is also shown by the nearly constant references in his shorter works to a more complete and final volume yet to come, and by the clear statement in the author’s own preface to this book. In that preface, he explains that only after finishing his study of human anatomy does he now feel capable of truly moving forward and uncovering the previously hidden knowledge of the soul itself. He refers to his preliminary studies, including the Introduction to a Rational Psychology, as being complete; and "so now, at last," he writes, "we may treat of the soul from principles, or synthetically" A "synthetic" approach in philosophy involves starting from established principles to explain specific facts, rather than working backward from observations (the "analytic" method). Finally, whereas he previously warned both himself and his readers against daring to enter the sacred boundaries of this supreme knowledge too early, he now boldly invites them to enter. He believes that his readers, if they have chosen to follow him this far, "will perceive what the soul is, what its state is in the body, and what its state is after the life of the body."

It seems remarkable that a work representing the peak and conclusion of Swedenborg’s entire series of scientific and philosophical writings remained hidden in manuscript form for a hundred years before being discovered and published in the Latin edition by Dr. J. F. Immanuel Tafel. It is hardly less surprising that nearly half a century has passed before an English translation was provided. The immense importance of this work is plain to see from the evidence we have presented—whether we judge it by the high value the author himself placed on the subject matter, or by the diligence and passion with which he pursued the exhausting studies necessary to produce it.

We wish to add a few thoughts on its value, viewed in terms of how this work relates to the history of philosophy in general, and specifically to the later theological portion of the author’s writings.

As we remarked at the start, the single desire and goal driving the entire series of Swedenborg’s scientific and philosophical writings was his "search for the soul." This single aim provides the key to understanding Swedenborg’s mission in the worlds of science, philosophy, and theology.

The twofold goal of his search was to know the nature of spirit and its relation to matter—or, as the author frequently phrases it, "a knowledge of the soul and of its interaction original: "intercourse"; meaning the communication or connection between the spiritual and the physical with the body." If we view the body as the "larger body" (the natural world) and the soul as the "larger soul" (the spiritual world), the knowledge of the soul and its interaction with the body becomes the same as the knowledge of the spiritual world and its relation to the natural world. This is primarily the subject of the descriptive parts of the author’s theological writings.