Selections usually need no justifications. Some justification, however, of the treatment accorded Spinoza's Ethics may be necessary in this place. The object in taking the Ethics as much as possible out of the geometrical form, was not to improve upon the author's text; it was to give the lay reader a text of Spinoza he would find pleasanter to read and easier to understand. To the practice of popularization, Spinoza, one may confidently feel, would not be averse. He himself gave a short popular statement of his philosophy in the Political Treatise.
The lay reader of philosophy is chiefly, if not wholly, interested in grasping a philosophic point of view. He is not interested in highly meticulous details, and still less is he interested in checking up the author's statements to see if the author is consistent with himself. He takes such consistency, even if unwarrantedly, for granted. A continuous reading of the original Ethics, even on a single topic, is impossible. The subject-matter is coherent, but the propositions do not hang together. By omitting the formal statement of the propositions; by omitting many of the demonstrations and almost all cross-references; by grouping related sections of the Ethics (with selections from the Letters and the Improvement of the Understanding) under sectional headings, the text has been made more continuous. It is the only time, probably, dismembering a treatise actually made it more unified.
In an Appendix, the sources of the selections from the Ethics are summarily indicated. It would be a meaningless burden on the text to make full acknowledgments in footnotes. For the same reason, there has been almost no attempt made to show, by means of the conventional devices, the re-arrangements and abridgements that have been made. Every care has been taken not to distort in any way the meaning of the text. And that is all that is important in a volume of this kind.
Wherever possible Spinoza's own chapter headings have been retained; and some of the sectional headings have either been taken from, or have been based upon expressions in the text. It would have been more in keeping with contemporary form to use the title On Historical Method or The New History instead of Of the Interpretation of Scripture; a chapter on Race Superiority would sound more important than one on The Vocation of the Hebrews; but such modernizing changes were not made because the aim has been to give the reader a text as faithful to the original as the character of this volume would allow.