The Natural

You are of course right in saying that 'natural' is a concept that's been heavily abused over the course of history, and personally I have enormous fun whenever I find an example of how perceptions change in time (the most recent I remember being blue and pink colour for girls and boys respectively before WWII); it's at the same time mind boggling and expanding exercise and anytime I would advise anyone to try and give it a thought.

What we need to do though, is define what we mean when we say 'natural'. You've mentioned the possible meaning of 'good'. The two that come to my mind are 'as it is, untouched' and the widely (and perhaps sadly) accepted usage that denotes 'accepted by the society'. If it takes society as a reference point it is already influenced by it, therefore: not natural in the former meaning, but cultured. I wouldn't perhaps call it an ideology, at least not always, because I think more often than not that influence - or training - is not recognized by the speaker. 

Anyone who visited a foreign country knows that for different countries different things are considered natural. There are plenty examples from Japan, but there's hardly any need to look so far. Even 'sandwich' means something different in the States and Poland. It follows that 'natural' is a word just as relative as 'this', 'that', 'they', 'here' or 'there'. It has different meaning based on the frame of reference which basically boils down to personal experience. Remember our talk on being foreigners to everyone else in the world? I think it's the same with being natural. One of my favourite quotes, from Juanot Diaz is 'If you didn't grow up like I did then you don't know (...)'. That, or the experience of Adult Children - that's all connected; it all clearly shows how what feels natural is shaped as one grows up, perhaps in early childhood. What is the extent of this training into 'natural' and how far back could we trace trying to find the original, 'truely uninfluenced' natural? Attempts were allegedly made to discover a natural language, the proto-language, by raising children in a controlled environment, under the care of foster-nurses that would not speak a word to them. These language deprivation experiments produced children like Kipling's Mowgli, unable to speak, to come up with their own language (cross-reference), leading to the conclusion that language is assimilated up to a certain 'critical age' - but not innate. Similarily, I believe that we'd eventually come to the conclusion that 'natural' is largely a social construct, but that there ARE some fundamental, universal needs common to human beings across all cultures: (from the list of needs in NVC).

Another thing that we might want to consider is the idea of 'untoched' itself. While it's relatively easy if you consider natural look - without make-up - in the 21st century it's, as you point out, practically a futile endeavour. (I don't intend to go into the make-up debate right now.) I think we can say that anything that man does makes the product unnatural. When we think about food for me an easy division is the use of chemistry or lack thereof. But I'm much more interested in the ideological and linguistic side of natural.