restricted to a numerus clausus of real rights but is in principle entitled to establish new, hitherto unrecognized, rights in respect of his or her land. This made it essential for the courts to devise criteria to determine whether such a new right is real and thus registrable, or merely personal. In practice these criteria have therefore been developed by the courts in the context of the registration of real rights in respect of land What is more, the development of new real rights land is confined to limited real rights(that is, real rights with regard to someone else's property) New or additional kinds of ownership(such as the beneficial or equitable ownership of English law) could not be developed in this way in South african law. 20 Finally, it should be pointed out that the statement that there is no numerus clausus of real rights in South African law is also true with regard to real rights in movables. There is, however, no example of a new type of real right developed by the courts in the sphere of movables. here the categories of real rights remain the trad itional ones of ownership, personal servitudes and pledge the courts have developed the following two criteria or requirements. I real and thus registrable To determine whether a particular right or cond ition in respect of land (a) the intention of the person who creates the real right(testator or contracting party) must be to bind not only the present owner of the land, but also his successors in title; and (b) the nature of the right or cond ition must be such that registration of it results in a subtraction from the dominium of the land against which it is registered The first requirement does not, generally speaking, present any difficulties. It is purely subjective in nature and entails an interpretation of, for example, the will or contract in question in order to determine the intention of the party or parties who created the right The intention to create a real right is not, however, enough. A right which, according to its inherent nature, is highly personal cannot be converted into a real right by intention alone. 22 Obviously there is also a need for an objective criterion which can be used in the process of determining whether or not a particular right can at all be classified as a real right. The second requirement mentioned above, the o-called subtraction from the dominium'test, 23 has been developed in case law to fulfil this function. However, as will be illustrated in the next section, the formulation of this requirement or test is easier than its practical application 3. The application of the subtraction from the dominium'test: Three brief case studies Like other civilian legal systems, South African law adheres to the unitary concept of ownership(or the uniform ity of ownership). This means that there is only one kind of ownership and that ownership cannot be fragmented, in the sense that there cannot be intermediate degrees of ownership 2I Van der Merwe in Van der Merwe and De Waal(n. 7)sect. 46. This exposition of the criteria was approved by the highest court in Erlax Properties(Pty )Ltd. v Registrar ofDeeds 1992(1)SA 879(A) 22 Hollins v Registrar of Deeds 1904 TS 603: Lorent: v Melle and Others 1978(3)SA 1044(T); chiloane v Maduenyane 1980(4)SA 19(W) 23The expressions dim inution of ownership, "burden on the land'or" charge upon the land'are also sometimes usedrestricted to a numerus clausus of real rights but is in principle entitled to establish new, hitherto unrecognized, rights in respect of his or her land. This made it essential for the courts to devise criteria to determine whether such a new right is real and thus registrable, or merely personal. In practice these criteria have therefore been developed by the courts in the context of the registration of real rights in respect of land. What is more, the development of new real rights in land is confined to limited real rights (that is, real rights with regard to someone else’s property). New or additional kinds of ownership (such as the ‘beneficial’ or ‘equitable’ ownership of English law) could not be developed in this way in South African law.20 Finally, it should be pointed out that the statement that there is no numerus clausus of real rights in South African law is also true with regard to real rights in movables. There is, however, no example of a new type of real right developed by the courts in the sphere of movables. Here the categories of real rights remain the traditional ones of ownership, personal servitudes and pledge. To determine whether a particular right or condition in respect of land is real and thus registrable, the courts have developed the following two criteria or requirements:21 (a) the intention of the person who creates the real right (testator or contracting party) must be to bind not only the present owner of the land, but also his successors in title; and (b) the nature of the right or condition must be such that registration of it results in a ‘subtraction from the dominium’ of the land against which it is registered. The first requirement does not, generally speaking, present any difficulties. It is purely subjective in nature and entails an interpretation of, for example, the will or contract in question in order to determine the intention of the party or parties who created the right. The intention to create a real right is not, however, enough. A right which, according to its inherent nature, is highly personal cannot be converted into a real right by intention alone.22 Obviously there is also a need for an objective criterion which can be used in the process of determining whether or not a particular right can at all be classified as a real right. The second requirement mentioned above, the so-called ‘subtraction from the dominium’ test,23 has been developed in case law to fulfil this function. However, as will be illustrated in the next section, the formulation of this requirement or test is easier than its practical application. 3. The application of the ‘subtraction from the dominium’ test: Three brief case studies 20Like other civilian legal systems, South African law adheres to the unitary concept of ownership (or the ‘uniformity of ownership’). This means that there is only one kind of ownership and that ownership cannot be fragmented, in the sense that there cannot be intermediate degrees of ownership. 21Van der Merwe in Van der Merwe and De Waal (n. 7) sect. 46. This exposition of the criteria was approved by the highest court in Erlax Properties (Pty.) Ltd. v Registrar of Deeds 1992 (1) SA 879 (A). 22Hollins v Registrar of Deeds 1904 TS 603; Lorentz v Melle and Others 1978 (3) SA 1044 (T); Chiloane v Maduenyane 1980 (4) SA 19 (W). 23The expressions ‘diminution of ownership’, ‘burden on the land’ or ‘charge upon the land’ are also sometimes used