A Classical View of the Intuitionistic Continuum
A Classical View of the Intuitionistic Continuum
复制标题
直觉主义连续体的经典观点
DOI:
10.1016/0168-0072(95)00050-x
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发表时间:
1996
期刊:
影响因子:
--
通讯作者:
J. Moschovakis
中科院分区:
文献类型:
--
作者:
J. Moschovakis
Stephen Cole Kleene was at heart a constructivist who treated unavoidable uses of the law of excluded middle the way early twentieth-century mathematicians treated uses of the Axiom of Choice. His work on recursive fimctions and the foundations of intuitionistic mathematics aimed at establishing the constructive viewpoint as a useful and comprehensible refinement of the classical. The number-realizability interpretation developed for intuitionistic number theory by Kleene [4] and formalized by David Nelson [181 gives a classicaily comprehensible “outer model” of the theory; this work complements GGdel’s earlier negative translation[11, which shows that intuitionistic number theory “is only apparently narrower than the classical one, and in truth contains it, albeit with a somewhat deviant interpretation.” Giidel goes on to say,“Intuitionism appears to introduce genuine restrictions only for analysis and set theory; these restrictions, however, are due to the rejection, not of the principle of the excluded middle, but of notions introduced by impredicative definitions.” In order to communicate and argue effectively for these restrictions it was necessary to axiomatize a significant part of Brouwer’s analysis and set theory, a task which fell mainly to Brouwer’s student Arend Heyting. Unfortunately Heyting’s formalism did not lend itself to comparison with the classical systems and his analysis perpetuated a well-disguised circularity in Brouwer’s “proof” of his “bar theorem”(see [2], corrected in the third edition).Attracted by Brouwer’s view of the continuum as a structure whose elements are not all individually knowable, but about which (for this very reason) one can draw some powerful conclusions from which the classical mathematician shrinks, Kleene [lo] uncovered the axiomatic character of the “bar theorem.” He developed a usable