In Jainism, the terms "Vastu" and "Tattva" have distinct meanings:

Vastu (वस्तु):

• "Vastu" generally means "substance" or "entity."
• In Jain philosophy, Vastu refers to the fundamental realities or substances that make up the universe.
• There are six dravyas (substances) recognized as Vastu:

1. Jiva (soul) 2. Pudgala (matter) 3. Dharma (medium of motion) 4. Adharma (medium of rest) 5. Akasha (space) 6. Kala (time)

Tattva (तत्त्व):

• "Tattva" means "reality," "principle," or "truth."
• In Jainism, Tattva refers to the basic categories of truth that explain the path to liberation and the nature of existence.
• There are generally seven (sometimes nine) Tattvas:

1. Jiva (soul) 2. Ajiva (non-soul) 3. Asrava (influx) 4. Bandha (bondage) 5. Samvara (stoppage) 6. Nirjara (shedding) 7. Moksha (liberation) (Sometimes Punya and Papa—merit and demerit—are added as the eighth and ninth tattvas.)

Summary of the Difference:

• Vastu is about the fundamental substances that constitute reality.
• Tattva is about the fundamental principles or categories that explain the soul’s bondage and liberation.

Both are foundational concepts in Jain philosophy, but they address different aspects of Jain metaphysics.