Celsus: "no God or son of God has come down or will come down"

[Giuseppe]

We can't know if Celsus denied the earthly existence in the past of Attis, for example.

Thank you. That is my point, which was in response to your comment in your OP:

hence you agree with me that Celsus is evidence of a belief in true gods dying and rising uniquely in heaven and in outer space. Well.

Is Celsus a Zeus mythicist, an Attis mythicist, an Osiris mythicist, etc, just as he is a Jesus mythicist?

The answer is: we don't know, because Celsus doesn't detail his own views clearly.

wrong. The answer is: we know that Celsus is not an atheist. We know that the true gods about which existence Celsus didn't doubt, that these gods didn't exist (and didn't work) on earth but only in heaven.