What are some fundamental chasidic works of philosophy / theology?

Question

Which books are fundamental in terms of presenting the philosophy / theology of mainstream chasidut?

I know Chabad has Tanya, and Breslov has Likkutei Moharan.

Which sefarim are philosophically fundamental to non-Chabad, non-Breslov chasidim? Does this differ by sect? Are Tanya and/or Likkutei Moharan fundamental for them as well?

I imagine that R. Elimelech of Lizhensk's Noam Elimelech would feature on this list. What else is there?

I'm looking for philosophical works, not collections of stories or chassidishe vertelach, unless these are used (explicilty or implicitly) by chasidim to inform their philosophy.

Answer 1

In a comment OP notes interest in "anything really" but also what "chassidim themselves use to inform their philosophy as chassidim"; I'll attempt to list some of both types.

Of the same genre as Tanya or LM none come to mind, but there are many "classics" which from them different theological concepts and philosophies for Chassidism are drawn. I think the reason that there are maybe a handful of the former type is because the Chassidic masters didn't necessarily have a systematized arrangement of philosophies and possibly didn't even want to focus on such "scientific" systems. But the reasons and backdrop for this is somewhat off topic. My point is, much of the Chassidic ideas etc. are gleaned from the classics I mentioned. So to begin with, for one not so familiar with the Chassidic literature I'd suggest a perusal of Aryeh Kaplan's 1) The Light Beyond and 2) Chasidic Masters. Also worthwhile is Louis Jacobs' Hasidic Thought (as well as his couple entries in the EJ). A good anthology of Chassidic thought on a multitude of topics is Louis Newman's Hasidic Anthology.

Per Hebrew classics, besides those you already mentioned, I'd name: דגל מחנה אפרים, תולדות יעקב יוסף, קדושת לוי, פרי הארץ, מגיד דבריו ליעקב, עבודת ישראל. Although these are Torah collections, much Chassidic thought and doctrines are culled from different lessons given over by their respective authors. The בני יששכר is more kabbalistic bent although is also a classic. Then of course the later on in generations you go the more books were published and the more volumes were inducted into the "Hall of Fame", e.g. ערבי נחל, אוהב ישראל מאור עיניים etc.

Answer 2

Keser Shem Tov and Tzavaas HaRivash, along with Toldos Yaakov Yosef and Degel Machane Efraim are perhaps the earliest works that one can use to get a sense of the Baal Shem Tov's teachings. As the BeShT left no written legacy, his earliest students compiled his teachings into a number of sefarim.

As you get further down the chain of transmission you see divergences among the various chassidic schools of thought that resulted from the branching out of different tzaddikim and their students into the other areas of Europe; while the fundamentals still hold true, particular systems will emphasize different aspects of the path of the Baal Shem Tov, informed in part by their own areas of expertise as well as the demographic they were catering to/encountering in their milieu.

A fairly recent listing of what can be boiled down to the ten basic points of the Baal Shem Tov's path can be found as a stand-alone essay in the Divrei Shmuel of Slonim's eponymous sefer (I can't upload the page at the moment).

More recently, Belz has been putting out a series of sefarim that takes an in depth (yet accessible) look at chassidus as a conceptual framework entitled Mesilos b'Ohr HaChassidus.

Good luck!