四明十義書 1.175

1.175

若爾，豈唯觀成無外法可歷。理未顯時，若修外觀，亦無一法可為所觀，外色等法已為內觀遍觀畢故。此則內外兩觀皆不成也。不專內故，內觀不成；無外事境故，外觀不成。

If so, not only would there be no external dharmas to pass through after contemplation is accomplished, but even before principle has become manifest, if one were to cultivate external contemplation, there would also not be a single dharma that could serve as the object of contemplation, because external form and other dharmas would have already been completely contemplated by the internal contemplation. This means that neither internal nor external contemplation would be accomplished. Because one is not focused solely on the internal, the internal contemplation is not accomplished; because there are no external phenomenal objects, the external contemplation is not accomplished.