The idea of both nature and the human psyche being rooted in the 4 elements of fire, water, air, and earth is something you hear about from time to time because it was very popular among ancient Greek philosophers.
Later, I realized that ancient Jewish Sages also discussed the 4 elements, but I never paid much attention until reading Ahavat Kedumim (A Commentary on The Lost Princess) by Rav Ofer Erez.
There, Rav Erez presents a brief discussion of the 4 elements as they relate to the human psyche and how to use that knowledge for middot work.
That's when I realized this was a big thing in Judaism.
This realization was strengthened upon encountering Rav Itamar Schwartz's writings. Rav Schwartz leans heavily toward using the 4 elements as a tool to do teshuvah and rectify one's soul at the deepest level.
Also, Rav Schwartz provides a list of where the 4 elements are rooted in Jewish sources: Torah Sources of the 4 Elements (Hebrew Only).
It's important to note that even if a Torah book was only printed later, most of its sources are rooted in even more ancient sources that were either transmitted orally or written down in a book that got lost over the millennia.
(For example, some sources say that Avraham Avinu wrote several books and only one is said to be in existence today, but we no longer have the rest of them. Please see HERE for mention of that.)
Also, in Hebrew, the 4 elements are often referred in various sources as the 4 yesodot — but also the 4 yesodin, the 4 teva'im, or the 4 gufim, and maybe other terms.
If you look on page 3, section bet/2 of the above-linked pamphlet of sources, you'll see that Sefer Yetzirah Perek 3: Mishna 3 mentions the 3 amot (air, water, fire), stating that the heavens were initially created from fire, and the land (earth) was created from water, and that air is the a type of defining buffer between the fire and the water.
It explains other things about it too.
Anyway, I started to realize that the 4 Elements was an authentically Jewish way to understand personality and middot, and I started reading what Rav Schwartz says about it, yet I couldn't pin down my own elements and got lost in it all.
To use the system correctly, it's essential to know your base element and then the main influencing element, and then the next influence after that, and so on.
Recently, Rivka Levy published a new self-help book called People Smarts: The System: Understand yourself, understand others, and crush your stress.
The book also offers other helpful insights into understanding stress reactions and finding the balance in yourself.
If you wish to explore a personality system rooted in authentic Torah sources, People Smarts is a great place to start.