Greetings, Brother / Sister!
T-Squares as well as everyone involved being retrograde usually intensify all planets involved especially the apex ones, them being the key to solve the riddle of the T-Square so to say. In your case we see obvious accent on the 4th or 4th-5th houses. Uranus-Mercury-Jupiter/Saturn aspect is of intellectual talent while Moon-Neptune or Moon vs the same higher planetary composition shows artistic and/or intuitive talent. Moon-Neptune/Uranus is also of great prophetic talent & intuition, all might be connected to bloodline / nation / roots - both genetic and cultural ones or used in the 4th spheres realization listed in the links given below.
Here I said enough about houses and 4th house in general, it really has endless professional spheres involved with it as well as 10th one does. These two are of greater things.
Even if the sign isn't a water sign, can planets here produce some "watery" tendencies? But more importantly, can it indicate psychic giftedness with the 4th House which rules the subconscious?
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*Vent, kinda. Saturn is hitting a very sensitive area for me (+ a personal planet stellium) that’s honestly ruining my life. Funny enough Saturn passing through my 1st house was the best time of my life. But this one I can’t handle by any means and I don’t know what to do about it… +...
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But as with all greater things, in some of the Eastern nomadic tribal shamans there is a proverb: "do not turn your talent into a great suffering" and here we have an example of such:
My natal sun is in 15 degrees Leo, and I want to free it from its negative karma as it's conjuct Mercury (Rx), Lilith and MC. Should I approach this only using freeing workings, or using also Sun Squares would be effective? In the case of the Sun Square, should I approach it as a freeing...
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Same you might find with 4th house outer planet in ToZ website written by HPS Maxine. Outer planets represent much of what we usually try to use as talent and sublimate into building civilization, yet we have to remember that where we have these things we have ... not to say karmic debts, but rather ability to build something great, yet we have to work hard on it and build it in us from zero - talent is nothing without hard work, that is started from zero because talent is a thing that is built from zero.
What I mean by "from zero" is extremely important to understand right: outer planet might mean that this is either a talent that was already worked upon, then it might work out as genial and wunderkind, yet more often we see that instead talent was rather not worked upon at all and as a result its energies stagnated and strayed ending up with us seeing a problem such as destroyed childhood in the new lifetime etc. Eastern nomads still have this understanding: if you do not realize your talent in building something for your fellow mankind it will turn against you - just for not using it for a Purpose.
T-squares show that the apex planet topic is somehow intensified in your life. You say that RX Neptune in 4th is an apex of several T-squares and who knows what else configurations. RX Uranus - another apex of a T-Square - is in the same place. Due to the nature of these planets alone they show a lot of (stagnated?) talent already, as well as extreme emphasis on the 4th or 4th-5th houses spheres in talent realization. See in above links to find professions or spheres these talents might be found in.
Such an emphasis might show that these talents either went stray and stagnated from past lives, then they might have already made some havoc in 4th-5th houses in this or that way. For the havoc to stop these energies must be re-directed into the needed riverbed. On the other hand if these did not cause any havoc at all this is a very good sign of them being realized talents from the past and you already taking a right path in the past so now instead of being scattered they are awaiting for you to awaken them and to renew your path.
Humans exist to self-realize and build civilizations, not to lead unimportant mediocrity existences, empty of feat. If they do the last, their higher energies stagnate and cause all kinds of havoc.