One of the things I (and I think we collectively have done to a great extent) is forgotten about or neglected ontology as “tutorial”. We used to talk about this way back in TAMBIS days and others did so as well. The idea is that by looking at an ontology I can learn about a field of interest. Our idea in TAMBIS was that one should be able to look at the TAMBIS ontology and learn about the basics of molecular biology and an operational aspect of bioinformatics (though this exact idea was never explored or evaluated). Ontologies are often described as the “background” knowledge of a discipline; they contain the entities in a domain, their definitions, descriptions and inter-relatedness. From this, a “reader” of an ontology should be able to get some kind of understanding of a domain.
With an ontology, there are two ways I can learn about a field of interest: First, I can look at an ontology for that field, explore it and from that derive an understanding of how the entities of that field “work”; Second, I can write an ontology about that field and, in doing so, do the learning. This latter one only works for small topics or learning at a fairly superficial level. I’ve done this for heraldry; cloud nomenclature; anatomy of flowers; plate armour; galenic medicine; and a few others. This isn’t scalable; we can’t all write ontologies for a field of interest, just to learn about it. I have, however, found it a useful way to help myself structure my understanding, even if the resulting ontologies rarely, if ever, amount to very much at all (these have also largely been for fun and not an endeavour to drive some research).
Is this tutorial aspect of ontology going to give a full understanding? For most ontologies of which I’m aware, looking at that ontology will not act like a college course in that subject area. Looking at an ontology is more like looking at an encyclopaedia; it is a list of things and descriptions of those things, which is all an ontology is really trying to do. A so-called reference ontology can fit into this encyclopaedic role well; an application ontology should do so, but just for that application area. However, I should be able to look at an ontology or a collection of ontologies and get a decent overview of a domain.
Having said this, however, we can make quite a good encyclopaedia from an ontology or set of ontologies, especially if there are an adequate number of semantic relationships between entities, as well as good editorial and other metadata around those entities. I say “ontologies” as just having an encyclopaedia or ontology of molecular function (as an example) tells me what molecular functions there are and how they’re organised, but it doesn’t give me, as a learner, much of a biological context. This isn’t the fault of the ontology; I just need to look at a broader picture of biology to really learn anything. If I could ask questions such as “what molecular functions exist in the mitochondria of mammals and in what processes do they participate”, then I have something to work with (I suspect). There then, of course, remains the question of how all this information knowledge should be presented. I feel there’s mileage in a standard sort of encyclopaedic form, using the label (term), synonyms, natural language definitions,, together with the structure of the ontology to present something useful.
I’m still sort of taken with the idea of ontology as tutorial; I should be able to look at the ontologies from a field of interest and learn about that field of interest. It probably won’t be an in-depth learning; shallower even than that offered by the excellent resource Wikipedia, which can readily be used as an introduction to a subject area. However, I should be able to get a decent enough view of a field of interest from its ontologies that I can structure my learning from other resources.