What are the 'Heavenly Gods' (Ten-Gods) in Four-Pillar astrology?

The so-called 'Heavenly Gods' in BaZi refer to the Ten-God system—a set of symbolic roles derived from how other stems relate to the Day Stem. They are not literal deities but archetypal labels (Resource, Output, Officer, Wealth, Sibling, etc.) used to map social roles, psychology and life functions.

How the Ten-Gods are defined:
Using the Day Stem as the center, other stems are categorized by their elemental relation to that center:
1. Resource (Yin/yang distinctions: Direct Resource vs Indirect Resource): support, education, nurturing, stability.
2. Output (Direct/Indirect Output—Food/Expression): creativity, expression, children, performance.
3. Officer (Direct Officer vs Seven Killings): rules, authority, bosses, discipline, pressure.
4. Wealth (Direct Wealth vs Indirect Wealth): income, assets, partners, chance gains.
5. Siblings (Peer stars—Bi Jian, Jie Cai): friends, colleagues, competition, shared resources.

Applications:
• Social network model: Ten-Gods sketch how someone interacts with family, career, money, and authority.
• Psychological drives: e.g., Wealth indicates material desire; Officer points to status drive; Output shows need to express.
• Pattern building: Higher-level configurations (e.g., wealth-official balance, output restraining officer, resource supporting output) are used to evaluate life potential.
• Determining useful elements: After judging day-master strength, astrologers identify which Ten-God(s) are favorable (yongshen) and which are harmful (jishen).