In this question I asked about philosophies and in the answer Be-Happy writes following lines
But the warning is valid because apart from the accepted philosophy and systems there are also systems like Charvak which are faulty and wrong.
Why is charvaka-philosophy of bhoga marga (i.e. enjoyment of all samsaric things) considered wrong by us/advaitins?
Charvak philosophy is faulty and wrong not just because it is hedonistic in nature but mainly because it rejects the Vedas and mocks the concept of Shradha, Yajna, afterlife, etc.
Charvak school of thought accepts direct perception as the only source of knowledge. Hence, it says there is no soul, no God, no afterlife, etc. as they are not directly perceivable. All these system of sradha, yajna, puja, etc. are invention of the frauds to earn their living. Death is the final liberation hence one should take pleasure here while alive even by borrowing money from others. And there are many other such views that the followers of the system used to hold.
But the problem is that direct perception alone is not a valid source of true knowledge. The earth appears flat by direct perception, the sun appears to move around earth by direct perception, but these are wrong. Hence, other methods of proof like inference, comparison, scriptural testimony, etc. are taken into consideration to find out the truth. And by those standards other philosophical systems like Mimansa, Vedanta, etc. came to exist and they refuted the Charvak system. The origin of such a system was only to lure people away from the Vedic path.
