Another attempt at plain language

Peter Constable petercon at
Thu Sep 3 07:02:55 CEST 2015

Coincidentally, there has been a project going on within ISO TC 37/SC4 to create a Technical Specification, "Language resource management — Controlled natural language (CNL) — Basic concepts and general principles". 

I thought these excerpts from a draft might be of interest for this discussion (I'm extracting only a few portions, which I am assuming to fall within fair-use allowances of copyright laws):

controlled natural language
subtype of human language whose structure is restricted and whose ambiguity is resolved for a particular
NOTE 2 to entry A CNL is an engineered (i.e. constructed) language that is based on a particular natural language, but is
more restrictive as regards lexicon, syntax or semantics, while at the same time preserving most of its natural properties.


Over the years, CNL has been known as 'processable', 'simplified', 'technical', 'structured' or ‘basic’ language, but 'controlled natural language' is now the accepted term. A wide variety of such languages have been designed over the last four decades: they include Basic English (Ogden, 1930), Caterpillar Fundamental English (CFE) (Verbeke, 1973), Caterpillar Technical English (CTE), SBVR Structured English (OMG, 2008) and Attempto Controlled English (ACE) (Fuchs et al., 2006). They are used to improve translation and other communication between humans, and provide natural and intuitive representations of formal notations.


Although many properties of CNLs and their environments have already been identified... CNL itself has the four properties listed below...

1. It is based on one specific natural language (its 'base language').

2. The most important difference, but not necessarily the only difference, between the CNL and its base language is that the former is more restrictive with regard to lexicon, syntax and semantics.

3. It is an engineered (i.e. constructed) language: this means that it is explicitly and consciously defined, and is not the product of an implicit and natural process, even though it is based in turn on a natural language that is the product of an implicit and natural process.

4. It preserves most of the natural properties of its base language, and accordingly speakers of the base language can intuitively and correctly understand texts in the controlled natural language, at least to a substantial degree.

These four properties describe application domains rather than the languages themselves. The PENS classification scheme (Kuhn, 2014) adds four dimensions: Precision, Expressiveness, Naturalness and Simplicity.

It strikes me that point 3 in particular would suggest that CNLs are very much within the scope of BCP 47.


-----Original Message-----
From: Ietf-languages [mailto:ietf-languages-bounces at] On Behalf Of John Cowan
Sent: Wednesday, September 2, 2015 8:33 PM
To: Michael Everson <everson at>
Cc: ietf-languages at
Subject: Re: Another attempt at plain language

Michael Everson scripsit:

> This “plain” thing is a style of discourse, not a genuine language variant. 

Not too different from Boontling, in my view, which is mostly a vocabulary.

John Cowan        cowan at
"The serene chaos that is Courage, and the phenomenon of Unopened Consciousness have been known to the Great World eons longer than Extaboulism."
"Why is that?" the woman inquired.
"Because I just made that word up", the Master said wisely.
        --Kehlog Albran, The Profit
Ietf-languages mailing list
Ietf-languages at

More information about the Ietf-languages mailing list