Various Puranas and Itihasas explicitly mention Vishnu incarnating as Buddha to teach an anti-Vedic doctrine in order to deceive certain Asuras from their righteous path.
Kapila, the founder of the atheistic Samkhya school, is another figure who is mentioned in the Puranas and Itihasas to be an incarnation of Vishnu.
My question is do any Puranas or Itihasas deal with the reason why he, despite being an incarnation of Vishnu, teach an atheistic doctrine? Do any of the Puranas and Itihasas state that his main purpose was to delude people just like Buddha?
Note: Please avoid quoting from the Uttara Khanda of the Padma Purana in your answer.
Edit: I'm aware that certain Acharyas such as Adi Shankara and Baladeva Vidyabhushana believed in two different Kapilas who propagated two different Sankhya philosophies. However, Vijnanabhikshu was one such Acharya who believed that there was only one Kapila who was an incarnation of Vishnu and propagated a Sankhya philosophy which was purely atheistic in order to delude the masses. Perhaps, he has quoted any such Puranic or Itihasic verses to support his theory in his works.