--- a/spec/index.html	Wed Feb 26 11:10:52 2014 -0500
+++ b/spec/index.html	Fri Feb 28 17:50:46 2014 +0100
@@ -97,10 +97,13 @@
   The Linked Data Platform is putting together a set of requirements for <a href="http://www.w3.org/2012/ldp/wiki/AccessControl">Access Control</a>
   </dd> 
   <dt><a href="http://www.w3.org/2005/Incubator/webid/wiki/Identity_Interoperability">Identity_Interoperability</a></dt>
-  <dd>A Principal is a string that identifies  an agent directly ( by reference ) or indirectly ( via a property that relates the Principal to another identifier that directly identifies the agent. 
-Well known Principals for an agent are the OpenId Principal, an Account Name Principal, a WebID, a public key, etc.... 
-Usually each of these Principals come with different authentication protocols. 
-This document should show how one can transfer trust gained via one authentication procedure to another Principal, by relying on relations published between these identifiers in a Linked Data space tied to a WebID.
+  <dd>Agents can be identified in many more ways than via WebIDs. 
+A WebID is a direct identifier: it refers directly to an agent. There are also a large number of indirect identifiers, that is identifiers that refer to things ( usually not agents ) directly, but that only indirectly refer to an agent. 
+For example the initial http OpenIds, directly identify a web page, and indirectly an agent. 
+An account name is a string that refers to itself, but indirectly identifies an account, which itself identifies a person.
+A public key identifies a set of numbers, but indirectly an agent that knows the private key, etc....  
+Each of the identifiers then come with methods of verifying the referent.
+The Identity Interoperability document should aim to show how one can transfer trust gained via one authentication procedure to another identifier, by relying on relations published between these identifiers in a Linked Data space tied potentially to a WebID.
   </dd>
 </dl>