Declarative knowledge

Declarative knowledge is an awareness of facts that can be expressed using declarative sentences. It is also called theoretical knowledge, descriptive knowledge, propositional knowledge, and knowledge-that. It is not restricted to one specific use or purpose and can be stored in books or on computers.

Epistemology is the main discipline studying declarative knowledge. Among other things, it studies the essential components of declarative knowledge. According to a traditionally influential view, it has three elements: it is a belief that is true and justified. As a belief, it is a subjective commitment to the accuracy of the believed claim while truth is an objective aspect. To be justified, a belief has to be rational by being based on good reasons. This means that mere guesses do not amount to knowledge even if they are true. In contemporary epistemology, additional or alternative components have been suggested. One proposal is that no contradicting evidence is present. Other suggestions are that the belief was caused by a reliable cognitive process and that the belief is infallible.

Types of declarative knowledge can be distinguished based on the source of knowledge, the type of claim that is known, and how certain the knowledge is. A central contrast is between a posteriori knowledge, which arises from experience, and a priori knowledge, which is grounded in pure rational reflection. Other classifications include domain-specific knowledge and general knowledge, knowledge of facts, concepts, and principles as well as explicit and implicit knowledge.

Declarative knowledge is often contrasted with practical knowledge and knowledge by acquaintance. Practical knowledge consists of skills, like knowing how to ride a horse. It is a form of non-intellectual knowledge since it does not need to involve true beliefs. Knowledge by acquaintance is a familiarity with something based on first-hand experience, like knowing the taste of chocolate. This familiarity can be present even if the person does not possess any factual information about the object. Some theorists also contrast declarative knowledge with conditional knowledge, prescriptive knowledge, structural knowledge, case knowledge, and strategic knowledge.

Declarative knowledge is required for various activities, such as labeling phenomena as well as describing and explaining them. It can guide the processes of problem-solving and decision-making. In many cases, its value is based on its usefulness in achieving one's goals. However, its usefulness is not always obvious and not all instances of declarative knowledge are valuable. A lot of knowledge taught at school is declarative knowledge. It is said to be stored as explicit memory and can be learned through rote memorization of isolated, singular, facts. But in many cases, it is advantageous to foster a deeper understanding that integrates the new information into wider structures and connects it to pre-existing knowledge. Sources of declarative knowledge are perception, introspection, memory, reasoning, and testimony.