Regular commentator Scott  "Bao Pu," asks whether it is possible for humans to obstruct the natural unfolding of Way.  His query came from my own suggestion in an earlier post that there are moral "oughts" in the DDJ and that those "oughts" center on encouraging people not to obstruct the natural unfolding of Way.

This is a big issue and it gets to the heart of the Daoist understanding of the role of the human in Way.  

To begin, passage 77 of the DDJ suggests that the Way of humankind can run counter to the Way of heaven but that some people, "sages," can resist this human tendency and follow the Way of heaven.  This implies that people can naturally act upon their desires and their wills in ways that fall outside the Way of heaven.  It might be argued that this is, in fact, the very nature of humankind.  We should expect greed and avarice and power-mongering because those are all of piece of the Way of humankind.  But why, then, does the text go on to tell us that the "sage" – who is certainly a human – can get out from under the Way of humankind and act in accordance with the Way of heaven?  Why should such behavior matter?  And why is it valued?  I would contended that it is valued in the text, and valued positively.  The term "sage" is a term of positive valuation, a person who has come to follow Way and whose actions and non-actions in the world promise something better than the Warring States violence and coercion that surrounded the text in its own time.   Ames and Hall explicate this passage, in part, as follows:

…we…human beings create a vicious circle in which the rich get richer, and the poor get poorer.  Chapter 75 states what is a familiar refrain in the Daodejing: "The people's hunger is because those above are eating too much in taxes."  It is only the enlightened among us who are able to coordinate fully their participation in their natural, social, and cultural environments,and who in so doing, extend the way forward for all concerned.  The bonus, of course, is that while sagacious conduct conduces substantially to a thriving world, the persons responsible make no claims upon the dividends that such efficacious living produces. (197)

From this I would argue we could say the text is prescribing that we ought to act like a sage and live in an efficacious manner that supports the thriving of others.

There are other ought statements we could derive from the text:

    – We ought not to kill other people (passage 74);

    – We ought to avoid warfare unless faced with attack (passage 30);

    – We ought to be happy with simple pleasures of home and family and small scale community (passage 80 and 12);

But the passage that is most relevant in this regard is 53, which strikes me as a clear statement of the wrongness of greed:

Understanding sparse and sparser still I travel the great Way, nothing to fear unless I stray.

The great Way is open and smooth, but people adore twisty paths: government in ruins, fields overgrown and granaries bare,

they indulge in elegant robes and sharp swords, lavish food and drink, all those trappings of luxury.

It's vainglorious thievery – not the Way, not the Way at all.

That last line strikes me as clearly evaluative, and in its evaluation it suggests prescription: we ought not do those things mentioned above.  

For contrast to the David Hinton translation I use, here is the final line from Ames and Hall:

This is called highway robbery (dao), which ought not to be confused with way-making (dao). (160)

Notice a couple of things: they pick up on the little rhyme in the Chinese text; they translate "dao" as a verb, way-making, thus emphasizing its processual quality; and, this is the kicker, they chose to explicitly assert an "ought" statement is being made here. 

We could go on, and perhaps we should at some point because the problem of the human place in Way, from the Daoist perspective, is problematic.  But I will leave it here for now with the reassertion that, yes, there are ought statements that can be derived from the DDJ.