--- a/model/working-copy/towards-wd4.html	Mon Feb 06 10:05:46 2012 -0500
+++ b/model/working-copy/towards-wd4.html	Mon Feb 06 16:52:49 2012 +0000
@@ -172,16 +172,21 @@
 </section>
 
 
+<!--
 <section id='preliminaries'>
 <h2>Preliminaries</h2>
+-->
 
     <section id='conceptualization'> 
-<h3>A Conceptualization of the World</h3>
-
-
-
+<h1>Overview</h1>
+
+PROV-DM is a data model for describing the provenance of <em>Entities</em>, that is, of things in the world. The term "Things" encompasses a broad diversity of concepts, including digital objects such as a file or web page, physical things such as a building or a printed book, or a car as well as abstract concepts and ideas. One can regard any RDF resource as an example of Entity in this context. This section provides an non-normative overview of the main elements of the PROV data model. 
+
+<div class="note">Following Ivan, I am shy here to mention Resource in the RDF sense. It will help RDF-ers anchor the concept of Thing to something they understand</div>
+
+  
     <section id='section-entity-activity-agent'> 
-<h4>Entity, Activity, Agent</h4>
+<h2>Entity, Activity, Agent</h2>
 
 
 
@@ -193,38 +198,48 @@
 </p>
 
 
+<!--
 <div class="anexample" id="entity-example">
 An entity may be a web page at a URI, a file in a file system, a car or an idea.
 </div>
-
+-->
+
+<p>An <dfn id="concept-activity">Activity</dfn> is anything that can operate on entities. In particular, activities may produce, consume, transform an entity. Activities that operate on digital entities may for example move, copy, or duplicate them.
+
+
+
+<!--
 <p>In the world, <dfn id="concept-activity">activities</dfn> involve
 entities in multiple ways:  consuming them,  processing them, 
 transforming them,  modifying them,  changing them,  relocating
 them,  using them,  generating them, being associated with them,
 etc.</p>
+-->
 
 <div class="anexample" id="activity-example">
-An activity may be the publishing of a document on the web, tweeting, extracting metadata from a file, or driving a car.
+An activity may be the publishing of a document on the web, sending a tweeter message, extracting metadata from a file, or driving a car.
 </div>
 
-<p>An <dfn id="concept-agent">agent</dfn> is a type of entity that takes an active role in an activity such that it can be assigned some degree of responsibility for the activity taking
+<p>An <dfn id="concept-agent">agent</dfn> is a type of entity that can be associated to an activity, to indicate that it bears some form of responsibility for the activity taking
 place.
+
+<div class="note">I would postpone this. At this stage I see no reason why one would raise an immediate objection. Why repair a damage that has not been done. <p/>
+  
 This definition intentionally stays away from using concepts such as enabling, causing, initiating, affecting, etc, because many entities also enable, cause, initiate, and affect in some way
-the activities.  So the notion of having some degree of responsibility is really what makes an agent. </p>
-
-
-<p>PROV-DM considers agents as a type of entity so that the model can be
- used to represent the provenance of the agents themselves.  For
- example, a grammarchecker software may be an agent of a document
- preparation activity, but itself can have a provenance record that
- states who its vendor is.</p>
+the activities.  So the notion of having some degree of responsibility is really what makes an agent.
+</div>
+
+<p>An agents is a particular type of Entity. This means that the model can be
+ used to express provenance of the agents themselves.  For
+ example, a software for checking the use of grammar in a document may be defined as an agent of a document
+ preparation activity, and at the same time one can describe its provenance, including for instance the vendor and the version history.</p>
 
 </section>
 
 
 
     <section id="section-generation-usage-derivation"> 
-<h3>Generation, Usage, Derivation</h3>
+<h2>Generation, Usage, Derivation</h2>
 
 <p>Activities and entities are associated with each other in two different ways: activities are consumers of entities and activities are producers of entities.  For provenance purpose, we define the following notions of generation and usage. </p>
 
@@ -269,7 +284,7 @@
 </section>
 
     <section id="section-types-entities-agents"> 
-<h4>Types of Entities and Agents</h4>
+<h2>Types of Entities and Agents</h2>
 
 <p>There are some useful types of entities and agents that are commonly encountered in applications making data and documents available on the Web; we introduce them in this section. </p>
 
@@ -298,7 +313,7 @@
 </section>
 
     <section id="section-responsibility"> 
-<h4>Responsibility</h4>
+<h2>Responsibility</h2>
 
 <p>The key purpose of agents is to assign responsibility
 for activities.  It is important to reflect that there is a degree in
@@ -334,7 +349,7 @@
 
 </section>
 </section>
-</section>
+<!-- </section>  -->