four philosophical terms

the “huge theoretical debate” consists of.

Objective morality

The view that some moral truths are valid independently of what a particular society happens to believe.

Example:

Torturing an innocent person is wrong even if a society approves of it.

Applied to equality:

Human beings may possess some objective moral claim to equal dignity even if a society denies it.

Universal human rights

The idea that certain rights belong to human beings because they are human, rather than because a particular government grants them.

Example:

A person does not cease to possess basic human dignity merely because the law denies it.

Relativism

In this context, the idea that moral or social standards can depend substantially on a particular culture, society, or historical context.

A strong relativist position might say:

What counts as morally right or wrong cannot be assessed independently of the society's standards.

Universal content of equality

This asks:

Are there some things that equality necessarily means everywhere, or can societies determine entirely different meanings of equality?

For example:

One position might say:

Equality necessarily includes equal human dignity.

Another might argue that societies differ over what equality requires in practice—equal legal rights, equal political participation, equal social status, equal economic opportunity, etc.