Chen Yu certainly knew what the Soul of the Great Dao was.
If Wu Feixuan had not used this item back then, his Heaven-Wild World would never have transformed into a complete world, let alone possessed complete Dao laws. All of this was thanks to the existence of the Soul of the Great Dao.
It seemed that the Soul of the Great Dao was the final barrier to making the Heaven-Wild World complete. Back then, the desolate Heavenly Venerate seemed to have lacked precisely this Soul of the Great Dao, which was why he had used his own body as a guide to bring certain rules into existence within the Heaven-Wild World, allowing it to sustain powerhouses at the Heavenly Venerate realm at the time!
Chapter 1933