Clarified what is "out of scope" in README and CONTRIBUTING.md.

1 files changed, 10 insertions, 0 deletions

diff --git a/README b/README
index 6164693b9..cf662ffd0 100644
--- a/README
+++ b/README
@@ -40,6 +40,16 @@ representation of the document, and a set of writers, which convert
 this native representation into a target format. Thus, adding an input
 or output format requires only adding a reader or writer.
 
+Because Pandoc's intermediate representation of a document is less
+expressive than many of the formats it converts between, one should
+not expect perfect conversions between every format and every other.
+Pandoc attempts to preserve the structural elements of a document, but
+not formatting details such as margin size.  And some document elements,
+such as complex tables, may not fit into Pandoc's simple document
+model.  While conversions from Pandoc's Markdown to all formats aspire
+to be perfect, conversions from formats more expressive than Pandoc's
+Markdown can be expected to be lossy.
+
 Using `pandoc`
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