Editing Marginal concepts (section)

== Marginality ==

Constraints are conceptualized as a ''border'' or ''margin''.<ref>[[Philip Wicksteed|Wicksteed, Philip Henry]]; ''The Common Sense of Political Economy'' (1910), Bk I Ch 2 and elsewhere.</ref>  The location of the margin for any individual corresponds to his or her ''endowment'', broadly conceived to include opportunities.  This endowment is determined by many things including physical laws (which constrain how forms of energy and matter may be transformed), accidents of nature (which determine the presence of natural resources), and the outcomes of past decisions made both by others and by the individual himself or herself.

A value that holds true given particular constraints is a [[marginal value|''marginal'' value]].  A change that would be affected as or by a specific loosening or tightening of those constraints is a ''marginal'' change, as large as the smallest relevant division of that good or service.<ref name="wieser_ein">von Wieser, Friedrich; ''Über den Ursprung und die Hauptgesetze des wirtschaftlichen Wertes'' <nowiki>[</nowiki>''The Nature and Essence of Theoretical Economics''<nowiki>]</nowiki> (1884), p. 128.</ref>  For reasons of tractability, it is often assumed in [[Neoclassical economics|neoclassical analysis]] that goods and services are [[Continuum (theory)|continuously divisible]].  In such context, a marginal change may be an [[infinitesimal]] change or a [[Limit (mathematics)|limit]].  However, strictly speaking, the smallest relevant division may be quite large.