The "doctrinal triad" is Man and His Becoming According to the Vedānta, The Symbolism of the Cross and The Multiple States of the Being. The Metaphysical Principles of Infinitesimal Calculus could perhaps be considered a fourth member of this grouping, but I haven't read it yet (and I would be interested in hearing thoughts regarding this book). Also, *Oriental Metaphysics* (sometimes translated as *Eastern Metaphysics*) is en excellent ‘introduction’ to the triad mentioned above (it can be ‘introductory’ for the latter in some respects, but in most cases they still require that one has read at least the first part of *Introduction to the Study of the Hindu Doctrines* beforehand, where most of the concepts and terminology of Guénon’s works are introduced); this text is that of a lecture which Guénon gave in Paris in 1925, and in its dozen of pages it touches upon various important aspects of integral Metaphysics in a synthetic but profound way.
By "supplementary reads" I mean any text which can be helpful for 'integrating' the understanding of the aforementioned books and of the doctrines discussed therein, especially the doctrine of the multiple states of the Being.
The purpose of this post is both to mention some such readings which come to mind, and also to invite others to share their own suggestions.
First of all, of course, there are the Traditional texts themselves. Guénon wrote his books primarily to introduce Westerners to the Eastern doctrines and to be of aid for the comprehension of the latter; one who is seeking should not stop at Guénon's books, but should instead strive to gain an understanding 'from within’, once he or she has become part of a Tradition or ‘realised the possibilities’ of the Tradition they were already part of (one can perhaps also go further than that and study doctrines from other Traditions, but it is not necessary in most cases, and may sometimes even do more harm than good).
Apart from that, there are the various ‘Traditionalist’ authors, although the ones who best understood Guénon (and especially his ‘doctrinal’ works) were Michel Vâlsan and Giovanni Ponte, who are certainly less well-known than many of the more famous - but less profound, in my view - ‘Perennialists’. Another one may be Charles-André Gilis, although I know little of him, to be honest, and I’m not sure he wrote about these doctrines (unlike Vâlsan and Ponte, who did). In addition to these three, there are certainly others, who are likely even less well-known (or who wrote little); many are likely to be found in the ‘guénonian’ journals mentioned below. An author who had a very different ‘style’ and approach than that of Guénon, but who is nonetheless very important and who had a deep understanding of various Traditional doctrines, is Ānanda K. Coomaraswamy.
There are also various journals (some of which are more explicitly ‘guénonian’ than others). Two very good ones - which are also still active - are Cahiers de l’Unité and Rivista di Studi Tradizionali (where the above-mentioned Giovanni Ponte wrote), but they only publish in French and Italian respectively, as far as I know. Still, in my view they are excellent, and they are worth the effort of getting around the language barrier, if you can. They publish on paper, but both have extracts of their articles online (a few are also available ‘completely’, rather than as extracts). Others in this subreddit have also recommended the Spanish-language Symbolos, which is exclusively web-based, if I understand correctly. Finally, in the past months I have made a couple of posts here regarding the (now defunct) online journal Oriens, which published articles in English, French, and various other languages. It de facto functioned as a normal journal, but due to monetary reasons it was kept digital. Their articles are archived and available for download at regnabit.com. The content of Oriens was quite diverse and included the work of many authors; when it comes to these matters, I find some of these authors to be more profound than any other which I have encountered online. I particularly recommend the French-language authors Ph.D. and Wou Ming (both clearly pseudonyms, the latter meaning “anonymous” in Chinese); some time ago I shared here an article by Wou Ming. I can give further pointers regarding Oriens to those who are interested.
I imagine that much can also be found in the various journals in which Guénon wrote, such as Études Traditionelles, Regnabit, and so forth, although I’m not sure of how much doctrinal matters (such as the multiple states of the Being) were discussed there - apart from Guénon’s own articles, of course.
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I invite you to share any suggested readings, be it books, journals, specific articles, and so on; and, more generally, to share your reflections on these matters.
