Soon we have the complete works of Scri Aurobindo here on Holybooks.com. In the meantime you can read the 704 page volume 25 that consists of two works: The Human Cycle and The Ideal of Human Unity War and Self-Determination. The Human Cycle was first published in monthly instalments in
the review Arya between August 1916 and July 1918 under the title The Psychology of Social Development.The Ideal of Human Unity was written and published in monthly instalments in the Arya between September 1915 and July 1918. In 1919 it was brought out as a book. Sri Aurobindo wrote
a Preface to that edition which is reproduced in the present volume. He revised the book during the late 1930s, before the outbreak of World War II. References to political developments of the period between the world wars were introduced at this time, often in footnotes.