Kuang-Ming Wu (The Butterfly as Companion) contrasts Zhuangzi's philosophy with Buddhism in answer to some who have sought to equate them. Even when we do not go that far, there is a tendency, I think, to lump them together, yet they are widely divergent in many important respects. I will share Wu's points in this and the following post, but first want to clarify his and my purpose in making the contrast. Admittedly, it is difficult not to be partisan here since I (and Wu, I think) have chosen the way of Zhuangzi to launch our own paths to transcendent experience. Still, a contrast need not imply dismissal; Buddhism is clearly a viable spiritual option. What this contrast intends is to put Zhuangzi's thought into relief that we might better understand its uniqueness.
And, I believe, his philosophy was and is unique, not just with respect to other traditions, but also within the boundaries of Daoism itself. He was not, of course, a Daoist at all in the sense that the term was only retroactively applied to the tradition to which he came to be associated. In the end, to my admittedly limited scholarship, Zhuangzi' philosophy was essentially lost to Daoism early on. That he was later deified by Daoists only serves to demonstrate this point.
It also needs to be re-iterated in this context that this distinction making between two philosophies is not about a "wrong view" versus a "right view"; at best we could only speak of the most effective view, and I, at least, have no means of making that judgment. But this point, that is not about truth but about subjective experience without recourse to knowing 'how things really are', is also a point of divergence between Zhuangzi and Buddhism, which does, in fact, hold "right view" as one of its central pillars.
Here then are some of the ways in which Zhuangzi's (and Daoist) philosophy differs from Buddhism:
1) In Buddhism, "things are moving in many circles, co-causing and co-arising to annoy us, making us suffer." Things, together with existence itself, are the cause of our suffering. For Zhuangzi, things are "alive, co-arising, co-dying, and are equally important." In Buddhism, things are seen as part of the problem; for Zhuangzi, things are unfolding Dao and are affirmed as such. Ch'i Wu Lun, the title to the second chapter of the Zhuangzi, might be translated, Wu says, "as a description of how equally important things are." In a broad, though debated, sense Buddhism can be described as world-denying while Daoism is world-affirming.
2) Consequentially, Buddhism seeks to escape the world. Zhuangzi seeks to more thoroughly integrate with the world. "For Chuang Tzu, we are part of such live interdependence among things. We must let go of ourselves so as to overhear, accommodate, and truly participate in the delight of such life flip-floppings. We are awakened to an onerous participation in the vicissitudes of things-transforming." Buddhism seeks to escape the ever-changing; Zhuangzi seeks to unite with the ever-changing.
You can check out Scott's writings on Zhuangzi here.