Kevin Gray's Concept of Property

I am currently reading Kevin Gray's article titled 'Property in Thin Air' regarding the question 'What is property'. Kevin Gray proposes that the criterion for defining property is 'excludability'. Using this criterion to measure 'propertiness' of a subject, a plaintiff may succeed in his claim that his property rights had been expropriated by another so far that the other person had affected his control of access of the property. In contrast, if the defendant's action had merely prejudiced the plaintiff's access to the resource but the plaintiff had not control over the access of the resource, then there is no "property" to which the plaintiff can assert has been infringed upon.

I asked myself the question after reading this passage featuring this proposition of 'excludability' - Should the criterion of excludability be used to demarcate the extent of a person's property right in a subject?

I suppose there is a certain 'normative' aspect into the inquiry 'What is property' since the High Court of Australia in Victoria Racing and Recreation Grounds Co Ltd v Taylor have foud themselves diverging in their decisions due to the different opinion upon the concept of property. The minority judges found a misappropriation of "property" in the sheer fact that the defendatns had diminished the plaintiff's access to the benefits of certain resources. By contrast, the majority found that there had been no taking of "property", precisely because the defendants' conduct could never in any event have deprived the plaintiff of control over access to thsoe resources.

I think that Kevin Gray is most likely correct in his proposition of the criterion of excludability to defining property. Let me take an analogy to demonstrate why I believe this is so. I may have access to use an unoccupied classroom around law school at NUS to study. If another person had occupied the classrom before me, my 'access to enjoy the classroom' has been prejudiced. However, this does not mean that the other person has prejudiced me of any property rights since I had no control over the access over the classroom such that I could exclude this other person from using the room.