There were apparently many anti-superstitious atheists in ancient India. (I wrote of Ajita Kesakambali earlier.) Mostly, we know of them through their religious critics in Indian scripture.
One such passage is known a Payasi Suttanta, from perhaps the 6th century B.C. In it, a holy man, Master Kassapa, confronts an unbeliever, Payasi, about his non-belief in dualism, reincarnation, and karma:
Now at that time there came over Payasi an evil view of things, to this effect: “Neither is there any other world, nor are there beings reborn otherwise than from parents, nor is there fruit or results of deeds, well done or ill done.”
Notice right away that Payasi’s doubt about dualism, reincarnation, and karma are attributed to “evil” rather than thinking or reasons. It will remind Westerners of ancient Israelite scriptures which attribute non-belief to evil and corruption. Or, in philosophical parlance, the “noetic effects of sin.”
Still, Payasi is given a chance to give his reasons for doubt. Master Kassapa asks:
Have you… any proof to establish that [another realm, reincarnation, and karma] do not exist?
Note again the similarity to the Christian/Muslim tradition. Rather than expecting to prove his claim that there is truth to dualism, reincarnation, and karma, the holy man asks Payasi to prove they are false. One wishes Payasi would have protested, but he does not.
First, Payasi says he knew some very evil men and some very good men and he got them to promise that if they died and were reborn in a lower or higher state they would go and tell Payasi about it so he would know that what the holy men said was true. But nobody has come and told him. Payasi thinks this is evidence against reincarnation and karma.
Master Kassapa replies with the ad hoc hypothesis that there are keepers of the “other world” who do not allow reincarnated persons to tell anyone of their experiences after death. He concludes:
Be this exposition a proof to you… that these things exist.
The ad hoc hypothesis is rather silly, as is the claim that this possibility proves that reincarnation is true. But hey, it’s ancient religious text. Par for the course.
Next, Payasi says he knows many holy men who live good lives believe in dualism, reincarnation, and karma. But if they believe their life after death will be so much better than their life on Earth, then why do they not kill themselves? Payasi concludes that even holy men do not believe there is life after death. (Or as Doug Stanhope put it, “If you really believe that death leads to eternal bliss, then why are you wearing a seatbelt?”)
Master Kassapa gives an astonishing reply, something to the effect of “You are foolish and evil, so you wouldn’t understand.” (Kassapa calls Payasi ‘Prince’.)
Once upon a time, Prince, there was a brahmin who had two wives. By one he had a son, ten or twelve years of age; the other was pregnant and near her time. Then the brahmin died. Now the boy said to his mother’s co-wife: “Whatever treasure there is, lady, or grain, or silver, or gold, all that is mine. There is nothing here for you whatever; make over to me lady, the heritage of my father!”
Then the [co-wife] made answer to him: “Wait, my lad, till my child is born. If it will be a boy, one portion shall be his; if a girl, she shall wait on you.”
But the boy reiterated his claim again and yet again. Then the [co-wife], taking a sword… ripped up her belly, saying, “If I can only find out whether it is a boy or a girl!” Thus did she destroy both her own life and her unborn infant and her wealth also, through the foolish and thoughtless way in which, seeking a heritage, she met with ruin and disaster.
Even so you, Prince, foolish and thoughtless that you are, will meet with ruin and disaster by seeking, without wisdom, another world. Moral and virtuous… brahmins do not force maturity on that which is unripe; they, being wise, wait for that maturity. The virtuous have need of their life. In proportion to the length of time such men abide here, is the abundant merit that they produce and accomplish for many…
Let this be a proof to you, Prince, that there is another world, that there is rebirth [and] that there is fruit and result of deeds well and ill-done.
Wowza. So non-believers are just too stupid to understand – as stupid as a pregnant woman who cuts herself open to discover the sex of her unborn child.
Next, Payasi suggests they could put a live man into a large jar and seal it with leather and cement, then put it in a fire so the man roasts to death inside. Then they could take the jar out of the fire and uncover the top, and if they see no soul escape, this would show there is no soul.
Master Kassapa replies that souls are invisible, so this would prove nothing.
We’re still playing the same game, 2500 years later.