(2) The medical and dental services issue: Likewise, as noted by Hayne, Crennan and Kiefel JJ[96], the foundation for the appellants' challenge to the constitutional validity of the identified provisions of the Act was only the prohibition upon "civil conscription" in the bracketed phrase in s 51(xxiiiA) of the Constitution. The appellants did not mount a separate challenge based upon the contention that all, or any, of the provisions impugned would, in their true character, take the Act outside the "central area" of the power provided by s 51(xxiiiA). Conventionally, a broad approach is adopted to the "central area" of such a grant of power, given the myriad circumstances for which the Parliament might decide to enact laws on that and related and incidental matters. Nevertheless, a point could arise as to the validity of a particular federal law where, for example, in its true character, an enacted provision was a law to achieve other and different purposes. The mere fact that a law was addressed to medical or dental practitioners, their actual or potential patients or healthcare issues generally, would not render it valid under s 51(xxiiiA) if, properly characterised, the law was not one with respect to the "provision" of "medical and dental services". Because this issue was not canvassed in these appeals, it can likewise be put aside; and