In some contexts, the use of the word "orthodox" seems to have nothing to do with these historic markers of Christian faith. Indeed, in many cases "orthodox Christianity" means only one thing: a particular view of sexuality and marriage.Which raises the obvious question: is there such a thing as a heretical anthropology? While I tend to agree with Smith (at least in terms of the somewhat narrow terms of the question as he has defined it), I think the more complicated answer is this: while there is no anthropological heresy, there are anthropological conditions for the possibility of orthodox or heresy. That is: some conditions for the possibility of heresy/orthodoxy have to do with assessing human creaturehood.
What does this mean? I think there are a number of implications, but first, note that I am not trying to heresy hunt, as the expression has it. I am merely following up Smith's observation about the broad use of the term orthodoxy. And of course, there are plenty of theologically driven questions to ask about when it comes to anthropology such as marriage, the role of sexuality in human identity making, the ethical propriety of genetic therapies etc.etc.
So, while I doubt whether one could stipulate an anthropological orthodoxy per se, there are plenty of candidates for false anthropologies floating around that would make for a difficult starting point (or backdrop if we are trying to avoid expressing ourselves in a Schleiermacherian mode) to affirming the Christian creed.
For instance, if one were to articulate human capacities in terms of an inherent perfectibility, that would seem to rule out the need for salvation. The number of ideologies or thinkers whom we might link to an idea of human perfectibility seem clear enough at the outset: extreme nationalists cite the glory of their nation, doctrinaire socialists cite the infallibility of the state, fascists cite some mystical idea that unites the powerful against a disheveled scapegoat. Each of these ideologiues suppose an ideal to which human persons can aspire without worrying about any inherent flaws in our way.
But, are there Christian theologians who believe - inadvertently - in human perfectibility, such that it places pressure on their ability to affirm the creed? Does the condition for the possibility of denying creedal orthodoxy exist in the fields of philosophical and theological anthropology?
I think the answer is yes, and perfectibility is often dressed up with reference to plasticity or malleability. These are philosophical terms that denote a certain interpretation of human freedom, but the scope of the freedom that is implied is very wide indeed. How we measure the goodness of human beings alongside the inevitable character of sin is a difficult task, a task that hangs over the last chapter of the book I am currently finishing. One thing seems certain: simply because an issue is not a question of orthodoxy and heresy does not seem to lessen its importance. Its importance may be indirectly related to a creedal matter. But that does not render it unimportant. Anthropology lurks between the lines of the creed, we can be sure.