[Ask HN] Fifth Generation Language (5GL)?

I read article «What makes a 5GL?»:

> You can't get a further level of abstraction than a 4GL so there can't be such a thing as a 5GL, just as you can't abstract further than meta-meta-metadata (which is what high-end repositories provide).

Why? Can anybody explain?

Moreover, wikipedia article about 5GL seems to be incorrect, as there is no 5GL. 5GL will change the world, so we will cannot miss that. ;-)

Links: http://www.it-analysis.com/channels/content.php?cid=9096 http://en.wikipedia.org/wiki/Fifth-generation_programming_language