Isvarakrsna (5th century AD) Whose name is connected with the Samkya Karika, probably the oldest of the six traditional systems of Indian philosophy which has its foundation attributed to the sage Kapila.

Samkya philosophy is said to have inspired Buddha

Gautama Buddha

Siddhārtha Gautama was a spiritual teacher from the Indian subcontinent, on whose teachings Buddhism was founded. In most Buddhist traditions, he is regarded as the Supreme Buddha Siddhārtha Gautama (Sanskrit: सिद्धार्थ गौतम; Pali: Siddhattha Gotama) was a spiritual teacher from the Indian...

, (though this is highly questionable as the Buddha predates this time by about 10 centuries) and probably Gnosticism

Gnosticism

Gnosticism is a scholarly term for a set of religious beliefs and spiritual practices common to early Christianity, Hellenistic Judaism, Greco-Roman mystery religions, Zoroastrianism , and Neoplatonism.A common characteristic of some of these groups was the teaching that the realisation of Gnosis...

 & Neo-Platonism.