Q: Is an aspect from Jupiter “debilitated” when it affects the cusp of Capricorn?
An aspect doesn’t have dignity, a planet has dignity. You have to understand that dignity is about the relationship of the guest to the host. The planet is a guest and the owner of the sign the planet is in is the host. Next you have to understand what an aspect is. It is a “dhristi” – it is a line-of-sight, by which a planet can cast a glance upon a different place. The glance is the glance of the host, it is not the host itself. The glance is not received by the host of the sign it lands in, because the glance is not a guest, it is just a glance. If someone looks at your house, it is a hell of a lot different than if they come into your living room. If they look into your house you get affected by that, but if they are actually in your house they are a guest. The aspect is a glance. it is the power of the planet transfered by a glance.
So the dignity of a planet is decided by it’s relationship to the planet who hosts the sign it is in. Therefore the glances that planet casts by aspects carry that dignity with them wherever they land.