In my previous essay I introduced the notion of using the notion of essential properties to address the question of whether James Bond must be a white man. I ran through this rather quickly and want to expand on it here.
As noted, an essential property (to steal from Aristotle) is a property that it must have. In contrast an accidental property is one that it does have but could lack. As I tell my students, accidental properties are not just properties from accidents, like the dent in a fender.
One way to look at essential properties is that if a being loses an essential property, it ceases to be. In effect, the change of property destroys it, although a new entity can arise. To use a simple example, it is essential to a triangle that it be three-sided. If another side is added, the triangle is no more. But the new entity could be a square. Of course, one could deny that the triangle is destroyed and instead take it as changing into a square. It all depends on how the identity of a being is determined.
Continuing the triangle example, the size and color of a triangle are accidental properties.  A red triangle that is painted blue remains a triangle, although it is now blue. But one could look at the object in terms of being a red object. In that case, changing the color would mean that it was no longer a red object, but a blue object. Turning back to James Bond, he has always been a white man.
Making Bond a black man would change many of his established properties and one can obviously say that he would no longer be white Bond. But this could be seen as analogous to changing the color of a triangle: just as a red triangle painted blue is still a triangle, changing Bond from a white to a black man by a change of actors does not entail that is no longer Bond. Likewise, one might claim, for changing Bond to a woman via a change of actor.
As noted in the previous essay, the actors who have played Bond have been different in many ways, yet they are all accepted as Bond.. . .