As a writer who covers disability issues, one of the most common questions I get is, “How come you say ‘disabled person’ instead of ‘person with disabilities’?”

It’s often born of a genuine desire to combat prejudice, reflecting the terminology someone has been taught to use. But it’s a question with surprisingly loaded implications.

The first phrasing, “disabled person,” is an example of what’s called “identity-first language,” in which the identity is placed before the person, acknowledging that it is a key part of someone’s experience. It does not imply that their disability is their entire identity, but rather, that it is entwined with their identity. You can probably think of a few other examples of identity-first language—”transgender person” or “Asian woman,” for example.

By contrast, “person with disabilities” uses “person-first language,” in which someone’s disability is treated as a secondary trait, ostensibly with the goal of focusing on the person and using the theory that people shouldn’t be defined or limited by their disabilities.

A simple terminology preference? Not exactly. Both are actually tied into two radically different models of conceptualizing disability.

The models are each rooted in the disability rights movement, even if they come from different “schools” of disability rights advocacy—and they are both the result of centuries of hard-fought battles to assert disabled people’s rights to live as fully included members of society. That fight is continuing: In the United States, for example, disabled people are still confined to nursing homes, sterilized without consent, segregated in school, discriminated against in employment, and much more, even though all of these practices are at least theoretically illegal.

Both person-first and identity-first language arose from a push to turn away from archaic and sometimes offensive terminology like “handicapped.” These terms are also about assertions of humanity and, for some, pride: They are a rejoinder to vague euphemisms that conceal and sometimes stigmatize disability, such as “differently abled,” “special needs,” and “handicapable.”

Identity-first language—using terms like “disabled person”—hooks into the social model of disability. This model positions disability as something created by society. A wheelchair user isn’t disabled because of the impairment that interferes with her ability to walk, but because society refuses to make spaces wheelchair-accessible. This model recognizes the existence of her impairment, but asserts that this is not the problem: Society’s refusal to include her is.

By contrast, person-first language about disability comes from the medical model, which is extremely popular among many policymakers, disability advocates, and nondisabled people in the United States. Again, under this framework, disability is an individual’s personal problem—and, often, something wrong with that person that should be fixed by medicine, if possible. Thus, our wheelchair user is disabled because of the condition that makes it difficult or impossible for her to walk. Society theoretically should accommodate her out of respect for diversity and human rights, as, for example, through the provisions of the Americans with Disabilities Act, a complaint-driven method of accessibility enforcement.

Some advocates feel there is a sense of the negative to this framing, as though disability is something unpleasant and bad. Meanwhile, proponents of person-first language, like venerable and highly respected disability rights organization The Arc, argue that this approach de-emphasizes disability, putting the subject’s humanity first and their disability second.

The distinction in thinking about this differing terminology really tends to lie at the heart of the movements that advance them. The social model takes on an institutional attitude, examining the social institutions and structures that contribute to disablism. The medical model tends to take on a more personal one, treating disability and ableism as private struggles. One is generally disability-positive (though it doesn’t expect or demand that everyone unreservedly love their impairments) and the other is generally disability-negative (though some adherents also belong to the disability pride movement).

This is a very simplistic breakdown of both models: There are other models of disability in use throughout the world, and advocates certainly integrate them in a variety of ways to meet the needs of their communities.

Under the social model, full access to society and treatment with dignity is an unquestionable human right. The medical model treats it more like a conditional one, often granted and taken away at the will of society—still extremely valuable and important, but not intrinsic.

When it comes to taking action, adherents of the medical model tend to focus first on pathology: identifying the causes of congenital conditions and preventing them, curing acquired disabilities, and approaching disability overall as a medical problem to be vanquished.

People who support the social model do not oppose treating and curing disease, but they distinguish between disability (a social condition) and impairment (an individual one): between eradicating identities and helping people lead the healthiest, happiest lives they can. Supporters of the social model join fans of the medical model in opposing systemic inequalities and public health problems that contribute to impairments and illnesses, such as the lead in Flint’s water and the toxic waste in Kettleman City, California. They invest resources in reforming social policies to promote inclusion, while also supporting public health treatment and prevention measures—like handing out condoms to prevent HIV or supporting seat belt laws to prevent catastrophic injuries in car crashes.

The social model focuses on preventing injustice by not viewing disability as an inherent personal problem. Instead, it prioritizes quality of life for disabled people, such as education reforms to change outcomes for developmentally, intellectually, and cognitively disabled youth who come from communities with environmental toxins. These impairments are very literally not a personal problem, but one caused by society, which should take responsibility for its actions.

If people are going to be born with, or acquire, impairments, they should be entitled to the same social opportunities as everyone else, including the right to disability pride. Since impairments are always going to be a part of life, it’s necessary to build a disability-inclusive society.

The rallying cry of the disability rights movement is “nothing about us without us,” a phrase that originated in Eastern European disability rights groups before spreading to South Africa and later North America. It speaks to the fact that the conversation about disability is often about disability, in a highly medicalized sense, rather than involving the participation of disabled people themselves—and that the disability community is fighting to change that.

Of course, using person-first language does not always suggest that the user follows the medical model, or vice versa. For example, the UN Convention on the Rights of Persons With Disabilities, which the United States has yet to ratify, articulates many of the points of the social model. While the document may use person-first language, it is a thoroughly social model-based assertion of disability rights, and is in some ways shockingly radical in its extensive assertion that disabled people are human beings with fundamental, inalienable rights.

It asserts that disability is a social, political, and cultural identity, and something that some people are actively proud of—that disability is not an inherent tragedy, a wrong, something to be fixed, but an important facet of some people’s identities. In that sense, disability has a function akin to gender, race, sexual orientation, religion, and other core aspects of people’s identities and sense of belonging.

However, it is important to recognize language’s history, and the way it is frequently and broadly used as shorthand for broader theories of change. The social model, and identity-first language, acknowledge disability as part of the diversity of humanity. It is not disabled people who are wrong or broken, but society, and it is society’s responsibility to fix it.

Since I write about disability from the perspective of a disabled person who is also concerned with systemic institutional oppression, I view the subject through the lens of the social model, which foregrounds autonomy, pride, dignity, and inclusion. However, the person-first model continues to be in widespread use and some people have a preference for it, including some of the people I write about.

As any responsible journalist should, I defer to the terminology my subjects prefer when describing them, which is why even I on occasion end up using person-first language to refer to disabled subjects—or, if you prefer, subjects with disabilities.