以下は，Ludger HonnefelderのScientia transcendens: Die formale Bestimmung der Seiendheit und Realität in der Metaphysik des Mittelalters und der Neuzeit (Duns Scotus - Suarez - Wolff - Kant - Peirce) (1990)のうち，Peirceに関連する箇所（第4部と結論部の一部）の読書ノートである．原文はドイツ語だが，引用にあたって英語に訳出している．
II. THE CONCEPT OF REALITY
3. Reality as the object of the definite opinion
[T]he distinctness of two mutually exclusive formal objects, according to Scotus, can only be of such a kind as to exist ‘prior’ to any act of cognition. What the two concepts grasp is thus something real, insofar as it constitutes its own formal content ‘prior’ to every act of cognition. Yet this real shows itself nowhere other than in cognition, and only in the terminus of cognition does it prove itself to be real. (pp. 392–393)
In Peirce, the criterion by which the reality of the universal concept is shown in each case is determined in a characteristically different way; yet the parallels to Scotus are once again striking. As for Scotus, so too for Peirce the fundamental assumption of real general concepts follows from the nature of our cognition itself. Nominalism is indeed right to assume that cognition is always cognition of a medium in consciousness. But it does not in the least follow from this that the validity of cognition must be restricted to the mere cognition of the medium, that is, to the cognition of representations in the receptaculum of our consciousness (8.16/II 471). Such a conclusion follows only if one begins from the problematic assumption already mentioned, that reality can only be ‘something independent of a representative relation’ (5. 312/II 239f.), and then draws from the indisputable difference between being-represented and being-real the highly questionable conclusion that the object of representation in a medium can never be real (5. 96). (p. 393)
→ Scotusは，形相性（formalitas）という，ens realeとens rationisの中間に位置するような存在論的領域を見出す．形相性は，それを把握する認識においてのみ現れるものでありながら，把握される内容は認識の働きに「先だって」あり，いわば事物の側に基盤を有しているという意味でリアルなものである．つまり，あるものが認識においてのみ存在する，あるいは認識作用の産物であるからといって，それがただちにリアルではないということにはならない．これはまさにPeirceの唯名論批判の要点でもあり，ここにPeirceとScotusの議論に同型性を見出すことができる．
With the reference to the mediated immediacy of our cognition, Peirce secures the fundamental assumption of the reality of its correlate. Yet no criterion has thereby been gained by which it can be decided whether a given concept represents truly, that is, whether it genuinely grasps reality. Unlike Scotus, who holds that a concept represents a reality when it can be shown as the simple result of a simple act of straightforward cognition, Peirce sees in the character of our cognition as an ‘immediate perception’ no sufficient criterion that a given concept is ‘truly representative’, that is, that it grasps reality. The claim to truth must rather be regarded as a hypothesis which itself requires justification (5.288/II 225f.). (p. 394)
→ 認識の「直接知覚」としての性格から，概念が実在を表象しているとするScotusとは対照的に，Peirceは，それだけではある概念が真に実在を捉えていると言うための十分条件ではないと見なす．Peirceにとって実在性を規定するのは，無際限の探究に末にたどり着くはずの理念的な「最終意見」である．
Without doubt, the appeal to the final opinion of the community of inquirers highlights the considerable difference between the path taken by Peirce and the teaching of Scotus. After Hume and Kant, Peirce could no longer fall back, in so immediate a way as Scotus does, on the noetic–noematic parallelism. (p. 395)
→ ScotusとPeirceの見解の相違を，HonnefelderはHumeやKantを経ているかどうかの相違に帰しているが，より根本的には近代科学の成熟が背景にあると考えることもできるだろう．
Nevertheless, the determination of reality carried out with its help is not so far removed from the Scotist approach as it might seem. The central significance that Peirce ascribes to semiotic representation within the category of Thirdness can indeed be understood as a radicalisation of the doctrine advocated by Scotus, namely of the cognition of the pure ad se as a cognition within the medium of a representation. And when Peirce emphasises that the reality of what is known, its objective precedence over thought, shows itself nowhere else than in its result ‘in the long run’ (8.12/II 467ff. and elsewhere), namely in its agreement with the final opinion of the community of inquirers, this too can be read as a radicalisation of the Scotist thesis: that the reality of formal contents, i.e. their precedence over all acts of understanding, manifests itself in no other way than in their result, namely in the conceptus proprii that formal contents are able to ‘bring about’ (terminare) in the act of cognition. (pp. 395–396)
III. The Understanding of ‘Being’
In considering Peirce, one must ask: by what guiding sense of ‘being’ is the explication of the concepts realis and realitas determined, upon which Scotus grounds his interpretation of the reality of the universal? And to what extent does this sense also find expression in Peirce’s reception of the relevant Scotist concepts? That there is a close connection between Scotus’s determination of the reality of the universal, within his doctrine of the natura communis and of the formalitates, and the central doctrine of his metaphysics, namely the doctrine of the concept of ‘being as such’, cannot be doubted. For Scotus, the two doctrines stand in a necessary, reciprocal relation: every attempt to determine the ‘reality’ of the essential determinations and formal structures grasped in our concepts presupposes an answer to the question of what ‘being’ means at all. (p. 396)
→ 「普遍者に関する実在論」の観点からPeirceとScotusの関係や，PeirceがSoctusから受けた影響については多くの研究の蓄積があるが，「実在性」概念のさらに根底にある「存在」（ens）の理解においても，PeirceはScotusの独自の学説を継承しているとHonnefelderは論じていく．
[A]ccording to Scotus, something is set apart from non-being in the sense of the intrinsically contradictory not first by the fact that it exists outside its cause, but rather because to its content there belongs formaliter ex se (‘formally from itself’) the possibility of being. The content’s own dispositio (intrinsic disposition) grounds that ratitudo (capacity-to-be, ontological aptitude) by which it is distinguished from the nothingness of the self-contradictory chimera, and on account of which it is, positively expressed, not repugnant to existence, and thus can be designated as ‘being’ in the broad sense. (p. 397)
→ Scotusにとって存在は"not repugnant to existence" (non repugnantia ad esse)であることによって規定される．
This ‘beingness’ shows itself as such only in thought, when the relevant content is grasped as that which is non-self-contradictory, as what is logically possible; but it is not constituted by thought. The intellect is only principiative (principle-giving) of the ground of that possibility which distinguishes something from the non-being of the chimera, insofar as—just as Scotus explains with reference to the divine intellect—it is the ‘first external principle’ for the fact that the relevant content is brought forth into being-thought. The possibility as such, however, belongs to the content itself prior to all thought, formaliter ex se. (p. 397)
→ 上記の箇所の続き．
‘Being’, as Peirce elsewhere states, encompasses in its broadest sense only the connection of subject and predicate expressed in the is, whether this is has the sense of actuality (‘actually is’) or of possibility (‘would be’) (1.548 / II 49f.). (pp. 398–399)
→ これはPeirceの「新しいカテゴリー表」からの引用．ここでのPeirceのBeingの理解は，Scotusのミニマルな「存在」の捉え方を引き継いでいる．
Even the reality that is recognisable and attested in the ‘final opinion’ is, after all, the reality of a ‘noumenon’ (8.13/II 469f.), and as such of the ‘nature of thought,’ so that the question remains, ‘wherein (ultimately) its reality consists’ (8.153). Is the ‘real’ that whose properties are independent of what anyone may think about them (5.405/III 271), or is the ‘real’ ‘the final objective opinion, which is indeed independent of the thought of any individual, but not in-dependent of thought altogether’ (7.336)? Must ‘reality’ be understood as the product of the act of thinking it, or does it merely find its expression in that act of the intellect? But this amounts to the question of whether intelligibility grounds the status of ‘being’ (in the broad sense described), or whether, conversely, beingness is the ground of intelligibility. But then, how is ‘beingness’ to be determined? (p. 400)
→ Peirceは，1890年代以降に「リアルな可能性」を認めることによってこの問題を解決したとHonnefelderは論じる．ここでも「可能的なもの」としての「存在」という，「存在」のScotus的な捉え方が前提となっている．
Only with this assumption of a ‘real possibility’, which shows itself in cognition but pre-cedes it and thus founds its status as ‘reality’, does Peirce succeed in connecting idealism or phenomenalism with realism in the form of a third path that leaves behind the extreme positions. The ‘scholastic realism’ thus proves to be an indispensable presupposition of the pragmatic realism formulated by Peirce. (p. 401)
With the theorem of the ‘real possibility,’ Peirce is not advocating an ‘extreme scholastic realism’ which—as he thinks against the background of his concept of nominalism—would go beyond Scotus himself (8.208). Rather, as the comparison shows, he is bringing into play precisely that understanding of ‘beingness’ which constitutes the core of Scotus’s metaphysics. (p. 401)
→ Peirceの自己理解では，「リアルな可能性」を認める彼の後期の実念論は，Scotusよりもさらに実念論的な「極端なスコラ実念論」であるが，Scotusの実際の学説と照らし合わせれば，この自己理解は必ずしも適切ではない．
When Peirce writes ‘that the third category—the category of thought, representation, triadic relation, mediation, genuine thirdness, thirdness as such—is an essential ingredient of reality, yet does not by itself constitute reality,’ (5.436), he is thereby attempting to express a relation between thought and reality such as Scotus determines through the connection of the criteria formaliter ex se and principiative per intellectum. (pp. 401–402)
Conclusion
For the question of whether and to what extent the formal determination of reality in Scotus and Kant’s approach can be brought into substantive correlation, Peirce’s solution provides a kind of counter-test. His attempt is explicitly both a “modification of Kantianism” (5.452) and a continuation of Scotist realism. (p. 459)
→ Peirceはどこかで「KantはScotusを読むべきだった」と書いているが，このことから窺えるように，彼の哲学はScotusの立場からKantianismを修正する試みであると言える．
In the second edition of the Critique of Pure Reason, Peirce sees proof that Kant, in developing the problem of idealism and realism beyond the restriction of the objective validity of our concepts to possible experience, and the consequent implication that then only our representations exist, relies on a third moment: “the flat denial that the metaphysical conceptions do not apply to things in themselves.” For Peirce, this third moment in Kant’s thought is “the very sun round which all the rest revolves” (6.95). (p. 460)
→ Peirceの引用は1903 Lowell Lecturesの第6講義より．
