anyone (a natural or legal "person") or anything with a separate existence that can be characterised through the dimension of its attributes. Usually requires a cognitive ability, such as human cognition, whereas an Identity doesn't - refer to the Turing Test, the Deep Blue chess program and the HAL9000 of "2001 -A Space Odyssey". An Entity may not need an Identity to access a "free" service, but needs at least one Identity to access a restricted service. In general an Entity cannot be owned, in the way that an identity can be owned, except in some legislative sense. Shareholders of a company may claim ownership, when they in fact only have some legal entitlement to the assets. Animals (eg horses) and humans (eg slaves) cannot actually be owned in the Identity sense, only possessed due to legal arrangements. Given that access credentials are issued to identities, why does this matter? Because it is the entity that applies for each identity, and the entity is legally responsible for the actions of the identity. It is often the entity that federates multiple identities.

In similar ways to this, Dr Sigmund Freud saw the person (entity) as consisting of the ID (identity) with an Ego or rational mind (additional identity attributes) and a SuperEgo or conscience (more identity attributes). Nietzsche called the ID "It" (identity) and investigated the life-affirming and life-denying qualities (attributes). Thus some people are seen to have multiple personalities, more than one ID each with its own ego (more than one Identity each with its own attributes).

Source: http://identityaccessman.blogspot.com/2006/08/identity-dictionary.html