脳神経倫理と生命倫理―生命倫理のバルカン化論争と応用倫理の収斂

Neuroethics and Bioethics―Implications of Balkanization Controversy

はじめに

　近年登場した脳神経倫理（neuroethics）は活発な議論を展開し，順調に発展しているようにみえる。国際学会（Neuroethics Society）が組織され，“The American Journal of Bioethics-Neuroscience”や“Neuroethics”といった専門のジャーナルも刊行され始めた。そうして蓄積されつつある議論では，神経科学（neuroscience）に関わるさまざまな倫理的問題が取り上げられるだけではなく，脳神経倫理そのものの位置づけが大きな関心の的となってきた。後者に関しては，当初，もっぱら生命倫理（bioethics）に対する関係が議論されていた。それが最近では，単に生命倫理だけではなく，遺伝子倫理（genethics），ナノ倫理（nanoethics），情報倫理（information ethics），環境倫理（environmental ethics）といった多様な応用倫理との関係も含めて検討が加えられるようになっている。ここでは，論点を拡大しながら続けられてきた論争を概観することで，脳神経倫理のみならず，他の関連分野を含め，いわば収斂するNBICテクノロジー（nano-bio-info-cogno convergent technologies）を対象とする包括的な応用倫理研究を組織すべきときにさしかかっていることを指摘したい。

Abstract

　There have been considerable disputes the positioning of neuroethics as a new field since its emergence in 2002.　It is the novelty of the neuroethical issues and the necessity for updated moral approaches to them that leading exponents of neuroethics have emphasized; advances in neurosciences have created an entirely new field of moral inquiries that the conventional bioethics had never noticed.　Futher,as neuroethics embraces the subdivision of ethics in neuroscience,it should take precedence over bioethics,which depends on the fundamental moral concepts without questioning their bases.　Many bioethicists have squarely opposed these insistences and thereby detected the claim of neuroethics exceptionalism: the asserted newness of issues comes mainly from the ignorance of exponents of this new field regarding accumulated bioethical inquiries,so that the overlapping concerns between bioethics and neuroethics are passed on to the future by them.　Moreover,bioethicists point out that the recent tendency of Balkanization in the field of bioethics could endanger the integrity of moral investigations.　Subfields of bioethics,such as geneethics,neuroethics,nanoethics and so on,originate consecutively,entail wastage of valuable time and money,and increase the risk of fragmentizing moral considerations in an inconsistent way.　By reviewing this controversy between neuroethics and bioethics,I argue that the relevant scientific investigations and technologies,which have appeared to promote the proliferation of bioethical sub-disciplines to date,are beginning to converge into 1 complex that demands not the division into subspecialities but the novel integration of bioethical inquiries: it is time to attempt the unification of bioethical applied ethics for moral considerations regarding nano-bio-info-cogno convergent technologies.