Table 1.

Organising knowledge: the epistemic agents and representational means

	Epistemic group	Representation type	Knowledge (base) type
I	Society	Demands Problem (e.g. patient, disease) Solution (e.g. diagnosis, prognosis, therapy) standards and funding policies	Common knowledge
II	Individual Scientists	Cognitive conceptualisation Implicit representation in mind Implicit semantics	Background knowledge of an individual scientist
III	Communities (clinical, biomedical, bioinformatical etc.)	Biomedical claims expressed in the scientific language - publications Explicit representation of domain knowledge Implicit semantics	Background knowledge of a scientific community
		Terms as units of biomedical claims Explicit representation of the terms - definition Implicit semantics	Distributed domain knowledge Various networks of biomedical terms
IV	Community (breast cancer)	Model for an ontology Explicit representation of a unifying conceptual model expressed in the scientific terms as a shared conceptualisation Semi-explicit semantics	Sub-domain knowledge problem related (merging domains)
V	Computer scientists Logics	Ontology Explicit formal representation of shared conceptualisation expressed in a formal language - formal ontology Explicit semantics	Formalised knowledge
VI	Computer scientists Engineering	Mapping ontology onto data records (metadata) Merged ontology model and information model - applied ontology Explicit representation and semantics	AI Knowledge Base (KB)
		Data (Instances) structured within database architecture Data models