Read this through. Necessary defining qualities? Your whole post implicitly assumes the existence of these magical qualities, which presumably reside somewhere just outside reality.
No. Would it have helped if I had put ‘human’ in quotes?
We refer to a particular category with the label ‘human’. The presence of certain properties is sufficient for us to assert that a thing is a member of the category. Calling a thing by that label is an assertion that those defining properties are present.
We do not need to have mortality as one of those properties to observe that all the things we call ‘human’ are mortal. If we find something that is a member of the category, but isn’t mortal, then we need to adjust our assumptions.
No. Would it have helped if I had put ‘human’ in quotes?
We refer to a particular category with the label ‘human’. The presence of certain properties is sufficient for us to assert that a thing is a member of the category. Calling a thing by that label is an assertion that those defining properties are present.
We do not need to have mortality as one of those properties to observe that all the things we call ‘human’ are mortal. If we find something that is a member of the category, but isn’t mortal, then we need to adjust our assumptions.