essentialness

Essentialness is the quality or state of being essential. In common usage it refers to characteristics that are indispensable for a thing's identity, function, or purpose. In philosophy, essentialism treats certain properties as essential to the things that bear them, properties without which the thing could not be what it is. These essential properties contrast with accidental properties, which a thing can lose without ceasing to be that thing. In modal logic and metaphysics, essential properties are often contrasted with contingent or accidental properties, and with necessary conditions that must hold for something to exist or be the case.

For example, the essential properties of a water molecule include its molecular structure H2O; its shape and density depend on the arrangement of atoms and are typically considered essential to water’s chemical identity, whereas the color of a sample is contingent. In ethics and identity discussions, essentialism posits that certain kinds have an intrinsic nature that defines them, though this view is contested.

Critics argue that essentialism can obscure variability, historical change, and cultural differences, and may lead to reification or stereotyping. Some contemporary approaches instead emphasize dispositions, relational properties, or de re vs de dicto readings of essences, and view identity as a dynamic or constructed feature rather than fixed.

Essentialness also appears in applied domains, such as lists of essential services, medicines, or skills, where what counts as essential is judged by practical necessity or policy objectives.