It is explained, I believe, by the supposition that Viracocha was the Lord of the Wind as well as of the Light.

Like all the other light gods, and deities of the cardinal points, he was at the same time the wind from them.

What has been saved from the ancient mythology is enough to show this, but not enough to allow us to reconcile the seeming contradictions which it suggests.
Moreover, it must be ever remembered that all religions repose on contradictions, contradictions of fact, of logic, and of statement, so that we must not seek to force any one of them into consistent unity of form, even with itself.
I have yet to add another point of similarity between the myth of Viracocha and those of Quetzalcoatl, Itzamna and the others, which I have already narrated.

As in Mexico, Yucatan and elsewhere, so in the realms of the Incas, the Spaniards found themselves not unexpected guests.

Here, too, texts of ancient prophecies were called to mind, words of warning from solemn and antique songs, foretelling that other Viracochas, men of fair complexion and flowing beards, would some day come from the Sun, the father of existent nature, and subject the empire to their rule.