How do you differentiate between epistemology and ontology?

Answer 1

Every science has its own ontology, epistemology and consequently its own methodologies.

Ontology defines the fundamental categories of reality. Domain ontology as distinct from formal ontology is related to focus of study. Each research field has its own ontology. A biologist, who studies ants, differentiates the ants' specific constituent parts, actions and contexts. Similarly a sociologist will have implicit and/or explicit presuppositions about categories of reality that are fundamental and related in the human and social systems she/he studies. Where formal ontology inquiry is to say something general about reality, domain ontology says something specific about different areas of reality.

Epistemology defines how we can know and reason that reality. As for domain ontology, each research field has its own epistemology: The maps applied by the biologist studying ants, are traditionally different from the maps applied by the sociologist in her/his studies of interacting humans.

The methodologies of each of these two scientists have followed as different systems of investigative techniques within their focus of study. The biologist and the sociologist traditionally apply different procedures for accomplishing and approaching the phenomena they focus on. They use different scientific methods studying different domains with different epistemology and ontology.