Is a secular outlook on the world an essentially modern phenomenon, or does it have precedents in the second-wave era?

It seems like we have a number of precedents in the past as well. For example Confucianism is a popular philosophy found in Chinese culture, looking at the teachings given by the Confucius it seems it had more of a practical and worldly approach than religious, the reason why Chinese elite were struck by the phenomenon. Another example is of Greek rationalism from where even the modern Western philosophy and secular thoughts seem to emerge. According to this religion had its own dominion separating scientific and philosophical issues. Similarly, legalism can be another example.