This site is currently being modified in order to conform to the
recommendations of the OASIS Published Subjects Technical Committee. (A
draft of those recommendations is temporarily available here in
anticipation of a stable location on the OASIS web site.) Please note
that there will be some broken links for the next few days. At the time
of writing, only the Biography and Music links are active. (Ontopia,
This site documents the published subject indicators and identifiers
defined by Ontopia. If you observe
a subject identifier of the form http://psi.ontopia.net/...
that does not resolve to a corresponding subject indicator, please notify us.
1. Topic types / classes
2. High level subject domains
3. Specialized subject domains
4. ISO standards
5. Single PSIs
Fixme: This stuff will shortly be moved elsewhere and modified to
conform to the OASIS Published Subjects Technical Committee
Many of these PSIs are recognized by Ontopia's software, and so using
them in your topic maps may make these behave more gracefully with
Ontopia's software. It is likely that some of these PSIs will be
superseded by standardized ones, in which case these PSIs will be
deprecated. Anyone should feel free to use these PSIs in their own topic
maps or topic map software.
- A type of association type that indicates that the association is
transitive. Let's call the association foo, if A foo B, B foo C, and foo
is transitive, then it follows that A foo C as well.
- A type of base name theme that indicates that the base name is a
plural name for the topic. So for the topic "dog", the name in the
plural scope would be "dogs".
- A type of occurrence that is the default occurrence of the topic it
is assigned to. This means that it is the primary occurrence of that
topic, such as the main article about a subject in an encyclopedia, the
definition in a thesaurus, the biography of a person, etc. Usually this
will be an external occurrence.
- A type of occurrence that is a description of the topic it is
attached to. Description occurrences are generally internal.
- A type of occurrence that is a metadata occurrence of the topic it
is assigned to. This means that the occurrence contains the value of a
property of the topic.
- An internal occurrence type used to hold copyright information about
a topic map. Used so that the topic map may define its own copyright
policy in a clear and well-defined way.
- Occurrences scoped by this theme are declared to be useable in a WAP
environment. This means that they are in a format that a WAP user agent
is capable of displaying.
- An internal occurrence type used to hold the time and date of the
last modification of the topic it is attached to, in YYYY-MM-DD HH:MM