Is There a Difference Between Its Essence and Its Existence?

There is no way to make sense of something whose essence and existence are not really distinct. If there is such a thing, then, it will be absolutely unique. The radius of a circle is really distinct from its circumference as proved by the fact that the latter is twice the former multiplied by pi. A real distinction between two things sometimes involves separability, but not always. For example, two dogs or a dog in its leg are really distinct and each might exist apart from the other. There's obviously a real distinction between the properties having a radius and having a circumference. This is not because when confining ourselves to circles, having a radius can ever exist apart fromhaving a circumference.