Earth and air, at cross purposes
Air weighs alternatives; earth wants a decision costed and executed. Libra will hold two viable options open for a long time because both remain genuinely viable, and Capricorn experiences the delay as a refusal to commit.
Libra, in turn, experiences Capricorn's decisiveness as a foreclosure of perfectly reasonable possibilities. Both complaints are fair. What makes the pairing workable is that they are complaining about different stages of the same process. Libra does the weighing and Capricorn does the committing, and a decision needs both.
Cardinal against cardinal
Neither sign is a follower. Both open subjects, set agendas and move first, so the question of who leads is live in almost every joint decision and never fully settles.
The square angle sharpens this. With opposite signs each holds a different territory, but a square puts them in the same territory with incompatible methods. Libra negotiates for consensus and Capricorn ranks authority, and the two procedures cannot both be followed at once. Whoever cares more about a given decision usually takes it, which works until the two care equally.
Venus and Saturn
Venus rules Libra and Saturn rules Capricorn. Traditional practice regards those two as reasonably well disposed to each other, and it shows: both signs value proportion, restraint and correct form, and neither has much patience with vulgarity.
The divergence is in what the form is for. Venus wants it because it makes life pleasant; Saturn wants it because standards hold things together. Where Venus and Saturn actually sit in the two charts decides which reading dominates. A Libra with Venus in Virgo runs closer to Capricorn than the sun signs suggest.
Where it grinds
Time. Capricorn treats work as the first claim on a week and Libra treats company as a legitimate one, so the calendar becomes the site of a slow argument that neither frames as an argument.
The second friction is conflict avoidance meeting bluntness. Libra defers a disagreeable conversation to keep the peace, Capricorn states the position flatly, and Libra then treats the flatness as aggression rather than as an answer. The deferred conversations accumulate, and they surface at inconvenient moments in a form neither recognises.
The Suns are the coarse layer
A square between sun signs is a statistical statement about a great many people and not a diagnosis of a couple. Plenty of these pairings run smoothly, and the reason is always somewhere other than the Suns. A tense sun-sign angle is a note in the margin rather than a conclusion.
The Moon accounts for what each needs at home, Venus for how warmth is offered, Mars for how a row proceeds. Compared across two charts, those three usually outweigh the sun-sign angle entirely.
Questions people ask about this
Is a square between sun signs bad?
It describes friction rather than failure. Squares tend to produce activity, and whether the activity is productive depends on the rest of the two charts.
Who leads in this pairing?
Both try, since both signs are cardinal. The workable version divides territory explicitly rather than leaving leadership to be settled case by case.
Do Venus and Saturn get on?
Traditional practice treats them as reasonably compatible, and the shared taste for restraint shows it. Their actual placements matter more than the rulership alone.
What should I compare instead?
Moon, Venus and Mars across both charts. Those describe two specific people rather than two large categories.