Modeling Rights in OWL

Wesley Hohfeld’s (1879–1918) discovery of an interrelated set of ‘incidents’ has had a profound effect on law and the analysis of rights, and is widely accepted (albeit with dispute around the edges). The Hohfeldian Analytical System is a formal system that can be used to analyze and relate different kinds of rights, their content, their agents, and actions to one another. The ‘incidents’ include:

  • powers
  • privileges
  • claims
  • immunities
Wesley Hohfeld (1879–1918)

Recently, I have been working with Mathias Brochhausen to implement them in an ontology in OWL that can be leveraged for knowledge representation of rights and obligations in domains like law, insurance claims, medicine…

Describing the incidents and relating them is easy for most of the rules in the system. For instance, relations like ‘Every power is a secondary rule and an active right’ are easy to treat with rdfs:subClassOf relations.

Other axioms are more difficult. Take for instance:

  • A has a claim that B φ if and only if B has a duty to A to φ.

There are any number of ways one might begin formulating this rule in a logical system. In OWL, however, one is limited by a) the (arguable) use of a three place predicate (i.e. X has claim/duty on Y to perform action Z) and b) a prohibition against repeating the appearance of a variable in a class axiom (for the same reason, one cannot axiomatize the class of all barbers who shave themselves). This leaves the task of enforcing some of these axioms outside of OWL in languages like SWRL, SHACL, and SPIN.

A developing draft of this work is now available on GitHub:

The Informed Consent Ontology (ICO)

There are many representations of informed consent in EHR systems. Such representations aid in clarifying which protocols are relevant to a research study, and what may be done with a particular biological sample taken from a patient. In this way, they aid in ensuring research can move forward while protecting patient rights.

I am presently aiding in a revision of the OBO Foundry Informed Consent Ontology (ICO), whose goal is to unite a series of ontological representations in order to track consent across the life cycle, from the moment consent is provided, through the transfer of that consent power to various other institutions, where it may be used to permit a particular research study.

The original version of the file developed by Oliver He and colleagues is available here and a development fork of its github repo containing this ontology is presently under development here. The development team and I are grateful to Oliver and his colleagues at the University of Michigan for the opportunity to work with them, and we look forward to presenting at ICBO2018. Comments and criticisms welcome. See our poster here.


Killing Animals for Food

Tyler Doggett (University of Vermont) and the good people at Wireless Philosophy put together this captivating and compelling video on the ethics of raising animals to be used as food. If you feel there’s nothing wrong with eating meat (or if you have an interest in the ethics of eating), take a few minutes and watch.


I’m in the process of putting together a medical ethics syllabus for a summer course at UB. It will cover issues at the ends of life (abortion, end of life care) and arguments concerning the goals of the medical profession, but I also hope to look at some issues in moral enchancement that more often come up in courses in neuroethics. Since the course is an online course, I would be interested in web links to videos and online content on these subjects.