Context: Hindu philosophy refers to a group of darśanas (philosophies, world views, teachings) that emerged in ancient India. The mainstream Hindu philosophy includes six systems (ṣaḍdarśana) – Samkhya, Yoga, Nyaya, Vaisheshika, Mimamsa and Vedanta. These are also called the Astika (orthodox) philosophical traditions and are those that accept the Vedas as authoritative, important source of knowledge.[note 1][note 2] Ancient and medieval India was also the source of philosophies that share philosophical concepts but rejected the Vedas, and these have been called nāstika (heterodox or non-orthodox) Indian philosophies. Nāstika Indian philosophies include Buddhism, Jainism, Cārvāka, Ājīvika, and others.

Question: What was the origin of Hindu philosophy?
Answer: ancient India

Question: How many main systems of Hindu philosophy are there?
Answer: six

Question: What are the main orthodox systems of Hindu philosophy called?
Answer: Astika

Question: What is the accepted source of knowledge in the Astika system?
Answer: Vedas

Question: What are the non-orthodox Indian philosophies that do not accept Vedas called?
Answer: nāstika

Question: How many darsanas are there?
Answer: Unanswerable

Question: What philosophy does Astika reject?
Answer: Unanswerable

Question: Which philosophy do both nastika and Astika philosophies accept?
Answer: Unanswerable

Question: What does Carvaka mean?
Answer: Unanswerable