These conditions functionally disabled them, and what is now known as the social model of disability emerged.
Or the term may serve to refer to the identity of disabled people.
Physiological functional capacity (PFC) is a related term that describes an individual's performance level.
In some countries, the law requires that disabilities are documented by a healthcare provider in order to assess qualifications for disability benefits.
Contemporary understandings of disability derive from concepts that arose during the West's scientific Enlightenment; prior to the Enlightenment, physical differences were viewed through a different lens.
In the early modern period there was a shift to seeking biological causes for physical and mental differences, as well as heightened interest in demarcating categories: for example, Ambroise Pare, in the sixteenth century, wrote of "monsters", "prodigies", and "the maimed".