Capricorn is the sign that rules responsibility. It's the traditional sign, governing maturity. This means that wherever you have Capricorn in your natal chart, you're tasked with responsibilities. It may be annoying at times, but it tends to fall on you because you can handle it.
Capricorn is an earth sign, along with Taurus and Virgo. The earth signs are practical, focused, and goal-oriented. They take things seriously, they put in the work, and they keep going.
Capricorn is also a cardinal sign, along with Aries, Cancer, and Libra. The cardinal signs are the leader, the ones who take charge and lead everyone as needed.
Saturn is the natural ruling planet for Capricorn, and Saturn is the teacher, the somber planet, the one who takes everything on. Saturn is not light, or goofy, and doesn't take it easy.
Put that all together, and Capricorn has to take charge as the leader, in a practical way as an earth sign, and take everything on somberly. This means Capricorn is where responsibilities are found in the areas of life ruled by the house in your natal chart that falls in Capricorn.
1st house: The 1st house is the house of the self, so a Capricorn 1st house can show you're someone others look to take responsibility. You may be someone who gets a lot heaped on, even at a young age, and people see you as responsible and capable.
2nd house: The 2nd house is the house of money, so a Capricorn 2nd house can show you're the financially responsible one, or at least strive to be. Others may look to you to take over financial situations, and feel you're capable of handling it.
3rd house: The 3rd house is the house of communication, so a Capricorn 3rd house can show you're responsible with your words and in conversations. You can be careful and cautious with what you say and how you say it, so others can trust you to handle the sharing of knowledge and ideas.
4th house: The 4th house is the house of home and family, so a Capricorn 4th house can show you're the responsible one at home and with family. You may take on a larger role in your family, even at a young age. You can be seen as capable with home and family matters.
5th house: The 5th house is the house of love, so a Capricorn 5th house can show you're responsible with matters of the heart. You can take love very seriously, and can be careful with those you love, not wanting to cause any hurt or stress of any kind.
6th house: The 6th house is the house of work, so a Capricorn 6th house can show you're responsible at or with your work. You may be seen as capable with the work you do, and others can trust you to do good work. This house also rules daily life, so you may be extra responsible in general.
7th house: The 7th house is the house of relationships, so a Capricorn 7th house can show you're responsible with others. You may be seen as capable in your relationships, and you can take commitment and partnerships very seriously. You may also attract many responsible people in your life.
8th house: The 8th house is the house of other people's money, so a Capricorn 8th house can show you're responsible with other people's finances and resources, and what you share with others. You can be seen as capable of setting up for the long-term.
9th house: The 9th house is the house of expansion, so a Capricorn 9th house can show you take expansion, exploration, and new experiences seriously. You can take on responsibilities associated with expansion, exploration, and new experiences.
10th house: The 10th house is the house of goals and naturally connects with Capricorn, so a Capricorn 10th house can show you can feel more at ease with your responsibilities, and handle them better overall.
11th house: The 11th house is the house of friends and change, so a Capricorn 11th house can show you're responsible with your friends and groups, and you take the responsibilities associated with change seriously. You can be responsible and considerate with change.
12th house: The 12th house is the house of the hidden, so a Capricorn 12th house can show you're responsible behind the scenes and in the background, and may be the one in charge. You can take on responsibilities from others to give them more room.
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