One of the most irrefutable facts proving that Hinduism is based on incest at its very foundation is the fact that the Vedas justify the beastly act of incest as a `sacred act'.
This was no doubt an outcome of the strict practice of `brahmacharya' which produced hoards of sexually starved psychopathic sadhus. It is these mad sadhu Brahmins, the authors of the concocted Vedas, who justified and legalised incast. Indeed, the Vedas enjoin incest as a kind of marriage. This fact was utilised by Brahma when convincing his daughter Sarasvati (also known as Padma) to succumb to his unlimited lust :
" 8. On seeing his beautiful daughter Padma, Brahma was sexually excited. He wooed his daughter and wanted to copulate with her. How could a daughter give consent to her own father? Padma refused. Brahma could not give up his desire. He began to quote the Vedas to convince her that there was nothing wrong in having sex with anyone, anytime, anywhere for the sake of giving birth to a child. " -- ( Puran )