ensure that all have access to primary schools at a reasonable distance from the home --, nor even finite65: this is why the question of which resources are available to the State still matters, even for the satisfaction of this minimum, and why we can hardly pretend that the "maximum available resources" vanishes once a definition of the "core content" is agreed. Another concern is that the definition of such "core content" may appear arbitrary, even if we limit ourselves to the first, "needs-based" requirement listed above. Katharine Young notes that the "core content" of economic and social rights listed in the Covenant is identified, alternatively, through four pathways, to which different justifications correspond.66 While the "core content" often is described as a "needs-based core", in which the "core" is derived from the basic needs of the individual, and particularly his or her survival needs, in line with the theories of development en vogue in the 1970s, other approaches also permeate the doctrine of the Committee. The "core content" is sometimes defined as a "value-based core", in which its contours are based on what is required by certain basic values such as the dignity of the individual, equality or freedom. Or, following a third approach, the "core content" may be seen as the result of a consensus that gradually takes shape across jurisdictions, across States (as expressed in international declarations in which governments profess their attachment to certain "core" dimensions of economic and social rights), or across experts of the concerned fields - such as public health, education or housing -- that correspond to the rights of the Covenant. Finally, a fourth approach would be to define the "core content" taking as a departure point the corresponding obligations, and asking what can reasonably be demanded from the State immediately, rather than being left to be subject to progressive realization: by paying attention to the remedial dimension associated with the "core content", we would be able to define the "core" based on what can practically be achieved. Young concludes that none of these approaches is convincing, and that taken together, they result in a doctrine that is neither principled nor, for that matter, legitimate. She finds that the various functions the "core content" approach to economic and social rights is meant to fulfil would be better served by abandoning the approach altogether. Instead, she suggests, we should rely on indicators and benchmarks (to track progress in the realization of the rights) and on classic notions of responsability and causality (where violations are alleged to result from certain measures being adopted by States that infringe on the enjoyment of economic and social rights).67 The inconsistency of current definitions of the "core content" may be simply an indication of the impasse we encounter when we try to bracket away the "progressive realization" clause of the Covenant, ignoring both its novelty and its subversive potential. Indeed, it shall come as no suprise that many commentators considered that the proposal made by Audrey Chapman might represent a step backwards, not forward -- in her own words "weaken[ing] the calls for a full implementation of the rights of the Covenant by concentrating on the most flagrant abuses".68 For instance, writing the right to health, Brigit Toebes notes that clarifying the "core content" of that right may encourage States to "put the elements not contained by the core into an 'indefinite'".69 Young makes a similar 65 This is true even for the requirement of non-discrimination. As illustrated by General Comment No. 20 adopted in 2009 by the Committee on Economic, Social and Cultural Rights, the prohibition of discrimination in international human rights law includes a) a prohibition of differential treatment that is based on any ground such as race, colour, disability, sex, sexual orientation and gender identity, language, religion, political or other opinion, national or social origin, property, birth or other status, and which has the purpose or effect of nullifying or impairing the recognition, enjoyment or exercise by all persons, on an equal footing, of all rights and freedoms ; b) a prohibition of any action or omission that, whether intended or not, disproportionately affects members of a particular group, in the absence of a reasonable and objective justification, thus constituting de facto discrimination; c) a duty to adopt special measures to attenuate or suppress conditions that perpetuate discrimination in order to eliminate de facto discrimination: such measures are considered legitimate to the extent that they represent reasonable, objective and proportionate means to redress de facto discrimination and are discontinued when substantive equality has been sustainably achieved. Thus, equality of treatment calls for an ongoing process of addressing inequalities. 66 Katharine G. Young, "The Minimum Core of Economic and Social Rights: A Concept in Search of Content", Yale Journal on International Law, vol. 33 (2008), 113-175. 67 Id., at 165. 68 Chapman, "The Status of Efforts to Monitor Economic, Social and Cultural Rights", cited above note 46, at 156. 69 Birgit Toebes, "The Right to Health", in Asbjorn Eide, Catharina Krause and Alan Rosas (Eds), Economic, Social and Cultural Rights: A Textbook (Dordrecht: Martinus Nijhoff, 2nd ed. 2001) 169-190, at 176 ("in addition to the core to be realized immediately, there is the remainder of a right which is to be realized progressively"). 14