尺鴳與大鵬的「小大之辯」是莊學中著名的寓言，但莊子作小大區分，用意不在突顯「物」的層次中個物間的差異，而乃由相對性的「小」與「大」之對立，隱喻價值性的「物」與「道」二層次之區分。而莊子「逍遙」的工夫，是以超越「物」的層次之「小」為起點，以達到、實現「道」的層次之「大」為目標，故在討論莊子的修養工夫論以前，不能不先對「物」、「道」二層次有所區辨與分別。

The main purpose of Zhuanzi's distinquishing "Xiao" and "Da" is not to emphasize the difference between the small and the great but to distinct "Dao" from "Wu". "Xiao-Yao" (untroubled ease) is a status only occurred with "Dao", therefore the discrimination of "Xiao", "Da" and "Wu", "Dao" is indispensible in Zhuangzi’s cultivation theory.