--- a/model/ProvenanceModel.html	Fri Aug 05 12:44:53 2011 +0100
+++ b/model/ProvenanceModel.html	Fri Aug 05 12:45:40 2011 +0100
@@ -938,8 +938,8 @@
 <li> The characterized thing denoted by <b>new</b> is derived from the characterized thing denoted by <b>old</b>
 <li> There exists an entity <b>X</b>, such that:
 <ul> 
-<li> <b>new</b> isIVP of <b>X</b>;
-<li> <b>old</b> isIVP of <b>X</b>;
+<li> <b>new</b> isComplementOf <b>X</b>;
+<li> <b>old</b> isComplementOf <b>X</b>;
 <li> <b>X</b> MAY have been asserted.
 </ul>
 </ul>

--- a/model/derivation.html	Fri Aug 05 12:44:53 2011 +0100
+++ b/model/derivation.html	Fri Aug 05 12:45:40 2011 +0100
@@ -93,6 +93,12 @@
 <h3>Derivation</h3>
 
 
+<div class='note'>This section remains very much work in progress.  Many issues have been raised and discussed, and for several of them, consensus still remains difficult to reach.  The presentation of derivation has been altered, and new names adopted, in the hope of clarifying this notion. Key outstanding issues include:
+<ul>
+<li> what is the exact relationship between entities attributes and derivation;
+<li> transitive nature of derivation.
+</ul></div>
+
 <p><dfn id="dfn-Derivation">Derivation</dfn> expresses that some characterized thing is transformed from, created from, or affected by another characterized thing.  </p>
 
 <p>PIL offers two different kinds of assertions by which asserters can formulate derivations. The first one is tightly connected to the notion of process execution, whereas the second one is not. The first kind of assertion is particularly suitable for asserters who have an intimate knowledge of process executions, and offers a more precise description of derivation, whereas the second does not put such a requirement on the asserter, and allows a less precise description of derivation to be asserted. From these assertions, further derivations can be inferred by transitive closure. </p>
@@ -148,22 +154,21 @@
 this means that the thing represented by <b>e1</b> has an influence on the thing represented by <b>e2</b>, which is captured by a dependency between their attribute values; it also implies temporal ordering. These are specified as follows:</p>
 
 <p>Given a process execution <b>pe</b>, entities <b>e1</b> and <b>e2</b>, roles <b>r1</b> and <b>r2</b>, if the assertion <b>isDerivedFrom(e2,e1,pe,r2,r1)</b>
-or <b>isDerivedFrom(e2,e1)</b> holds, then:
-<ul>
-<li> the values of some attributes
+or <b>isDerivedFrom(e2,e1)</b> holds, if and only if:
+ the values of some attributes
 of <b>e2</b> are partly or fully determined by the values of some
 attributes of <b>e1</b>.</li>
 
-<div class='note'>Always?</div>
+<div class='note'>Should this dependency of attributes be made explicit as argument of the derivation? By making it explicit, we would allow someone to verify the validity of the derivation.</div>
+</p>
 
-<li>that the use
+
+<p>Given a process execution <b>pe</b>, entities <b>e1</b> and <b>e2</b>, roles <b>r1</b> and <b>r2</b>, if the assertion <b>isDerivedFrom(e2,e1,pe,r2,r1)</b>
+or <b>isDerivedFrom(e2,e1)</b> holds, then
+the use
 of characterized thing denoted by <b>e1</b> precedes the generation of
 the characterized thing denoted by <b>e2</b>.
-
-
-</li>
-
-</ul>
+</p>
 
 
 
@@ -194,7 +199,7 @@
 This inference is justified by the fact that <b>e2</b> is generated by at most one process execution. Hence,  this process execution is also the one that uses <b>e1</b>.
 </p>
 
-<div class='note'>There is a suggestion by Simon that this notion of derivation is only meaningful in the context of an account. <a href="http://lists.w3.org/Archives/Public/public-prov-wg/2011Aug/0101.html">See email</a>.</div>
+<div class='note'>There is a suggestion by Simon that this notion of derivation is only meaningful in the context of an account. <a href="http://lists.w3.org/Archives/Public/public-prov-wg/2011Aug/0101.html">See email</a>.  It is not clear it is the case anymore. However, the inference above is only meaning full if unicity of generation hold.</div>
 
 
 <p>We note that the "symmetric" inference, does not hold.
@@ -226,21 +231,12 @@
 
 <p>Given two entities <b>e1</b> and <b>e2</b>, if the assertion <b>isEventuallyDerivedFrom(e2,e1)</b>
  holds, then:
-<ul>
-<li> the values of some attributes
-of <b>e2</b> are partly or fully determined by the values of some
-attributes of <b>e1</b>.</li>
-
-<li>that the use
+that the use
 of characterized thing denoted by <b>e1</b> precedes the generation of
 the characterized thing denoted by <b>e2</b>.
-
+</p>
 
-</li>
-
-</ul>
-
-<div class='note'>Does they hold too? SHould this be lifted up?</div>
+<div class='note'>Should we like isEventuallyDerivedFrom to attributes as we did for isDerivedFrom?  If so, this type of inference should be presented upfront, for both.</div>