Before embarking on this itinerarium mentis in intelligibile, it is necessary to make my own approach clear to the reader. How should one approach a thinker who himself wishes to approach Intellect? The answer, in a word, is transcendentally. That is, one must move beyond, transcend, any particular encounter with the world, whether that be sensible or intelligible being, and ask what makes being as such encounterable in the first place. Or conversely, what must mind itself be like given that it encounters being? What are the necessary conditions that make possible and are always already assumed in any encounter between mind and world?
I have adopted this admittedly Kantian approach for the following three reasons. First, the principle of charity requires that one try to make another author’s arguments as strong as possible. I believe recasting Plotinus’s claims about intelligibility as transcendental arguments obeys this principle, as such arguments possess, in the words of Robert Stern, “intriguing power” and “alluring promise.” This power lies in their beginning with some obvious or trivial experience admitted by even the most incredulous skeptic. In Kant’s case, he begins by assuming that there is something like mental composition, that some representation (either a sensible intuition or a mental concept) can be a composite of multiple parts, as when we encounter a white chair or think of a red circle. Not even a skeptic like David Hume would wish to deny that we can have such composite impressions or relations of ideas. Given such an obvious datum in experience, the transcendental philosopher shows that some things are implicitly assumed by such an experience, i.e. the conditions for its possibility. These, by contrast are usually far from trivial. For example, Kant argued that any composite representation, either in sensibility or in thought, requires the unitary and unifying activity of the synthetic a priori ego. If the transcendental philosopher succeeds in laying bare such conditions, he can force the skeptic into a dilemma. The latter must either accept that the agreed upon datum of experience always already presupposes certain non trivial claims about the subject or the world or he must, somewhat implausibly, deny that the original datum in fact obtains. That is, he would need to deny something like the rather straightforward proposition that human beings possess composite representations.
Kant’s relationship to Hume in the CPR is instructive as it is analogous to Plotinus’s relationship to the skeptics of his own time, notably Sextus Empiricus. In Enneads V.3 and V.5, Plotinus raises certain puzzles regarding the possibility of self-knowledge or reflexive self-awareness. Sextus Empiricus and Plotinus both wonder how such knowledge is possible if understanding is always of some object different from the subject who understands. Either the object and subject are different parts of intellection, in which case self-knowledge is impossible as the knowledge of one part by another is not self-knowledge or there is no object to be understood and thus no act of intellection.
Ultimately, Plotinus resolves such doubts by arguing that the activity of discursive thinking, the thinking of a part by a part, presupposes the activity of Intellect. The details of this argument will be dealt with in Ch.1. For now, we skip forward to the conclusion of V.3, which is that Intellect does indeed know itself qua an internally variegated whole. Its activity is nothing other than intellection of the intelligibles. These, in turn, are themselves individual acts of thinking constitutive of Intellect as little fires may be said to make up a larger Fire. Intellect is thus rightly called a thinking thinking of thinking(s) as such a fire would, in turn, be a burning-burning of burning(s). Consequently, when Intellect grasps the intelligibles, it grasps its own activity of thinking. Like Kant, Plotinus overcomes skepticism by showing how the possibility of some obvious phenomenon, like the ability to think discursively, is founded upon a deeper, non-trivial claim, e.g. that discursive reason is only possible insofar as it receives its indivisible concepts from the second hypostasis.
This parallel between Kant and Plotinus leads us to a second and stronger reason for adopting a transcendental approach to the Enneads. There is actually some basis for it in the texts themselves. Foreshadowing my argument in chapter one, Ennead V.1 is a prime example of Plotinus’s transcendental methodology. In this text, Plotinus wants to investigate what soul must be like if it is to know being. He posits that there must be some kinship or likeness (συγγένεια) between the two. In other words, Plotinus V.I by asking what the soul must be like if there is to be knowledge of τὰ ὄντα. That is, what are the necessary conditions on the side of ψυχή for knowledge of being? Or, as Plotinus himself asks:
Being what then, is the soul, that which inquires? It is necessary to know in order that it might learn first if it has the power to seek the first things and if it has the eye to see or even if it is fitting to search. If it is alien from the first things, why is it necessary to search? But, if it is of the same stock, it is both fitting for the soul to search and the soul is and capable of finding.
Consequently, as this dilemma, whether soul is akin (συγγενής) or alien (ἀλλοτρία) to being, prompts an inquiry into the conditions of knowledge, Plotinus’s method may be called transcendental in the relevant sense. For he seeks to lay bare the necessary conditions requisite to and presupposed by individual acts of discursive thinking.
While such an interpretation is neither original nor unique to this thesis, it is, to be sure, controversial and relatively new in the literature on Plotinus. Scholars such as Henri Ootshout, Yady Oren, Eric Perl, and Jens Halfwassen have noticed similarities between the Plotinus and post-Kantian transcendental idealism, especially as regards their affinity for ‘grounding’ or ‘transcendental’ arguments.
This modest overlap between Plotinus and Kantian argumentation is indicative of a larger scholarly trend of pointing out the “family resemblances” (Familienähnlichkeiten) between Platonic and post-Kantian forms of idealism. Such similarities were noted by none other than the great representatives of German idealism themselves as well as by eminent scholars of that tradition. Scholars of Plato and ancient philosophy, notably from the Tübingen School, have seen similar parallels. These mutually acknowledged similarities constitute the third major justification for reading Plotinus as a transcendental philosopher. Such a reading, while certainly contested, is within the bounds of acceptable opinion in the literature on both post-Platonic and post-Kantian philosophy.
Yet, even with this modest apology, two important qualification are in order. First, I do not wish to suggest Plotinus’s metaphysical account of intelligibility is identical to Kant’s transcendental epistemology. It is equally false to suggest that Plotinus is a mere anticipation of Kant as it is to claim that Kant simply recovered Platonic metaphysics. In this respect, I agree with the qualifications made by Oren, Oosthout, and Halfwassen. As Oosthout poignantly puts it, “we should not ourselves fall into the error of simply incorporating Plotinus into twentieth [or nineteenth]-century philosophy.”
It is surely anachronistic to restrict the three Plotinian hypostases to necessary logical presuppositions for the possibility of knowledge. As Oren warns, one ought to resist “reducing the hypostases, whether the One or the intellect, from real entities to explanatory principles.” Nothing could be further from the spirit or letter of Plotinian metaphysics, who nowhere suggests that the three hypostases exist only in human thinking or in ἐπίνοια. On the contrary, he preempts and denies such an interpretation in II.9. There he asserts, contrary to the Gnostics, that restricting oneself to mere conceptual distinctions in ἐπινοίᾳ is incompatible with the search for multiple intelligible hypostases (τῶν πλειόνων ὑποστάσεων ἀποστήσονται). The number of such really subsistent and distinct hypostases, as Plotinus has affirmed in numerous places (ἐδείχθη πολλαχῇ), is neither more nor less than three.
If one ought not reduce the hypostases and ideas to logical entities in the mind, one must equally avoid retrojecting Kantian epistemological dualisms onto Plotinus. That is, one must not imagine that distinctions like thing-in-itself vs. thing-for-us or noumenon vs. phenomenon have any basis in Platonic or Plotinian thought. The impossibility of such a reading is admirably explained by Vasilis Politis, who himself is recounting why Paul Natorp had to diverge from orthodox Kantianism in his reading of Plato. He writes:
This thrust in Kant’s transcendental approach is evidently wholly alien to Plato, who, if anyone, is engaged in a project of ontology. The theory of ideas, especially in such later dialogues as the Sophist, is a central part of such a project. Natorp looks to Plato for the original source of the transcendental approach, but what allows him to do so is his radical disagreement with Kant about the nature of this approach. Above all, Natorp rejects Kant’s view that if the nature of things is derived from the nature of thought and knowledge, then the account of the nature of things must fall short of an account of ultimate reality… Once Kant’s mistake is overcome, ie. the mistake of thinking that there can be a notion of things that is divorced from the conditions that make things knowable, there need not be a conflict between the transcendental approach, on the one hand, and metaphysics in the traditional sense of ontology, on the other. So Plato, as Natorp understands him, is not engaged in transcendental epistemology at the expense of ontology-that would indeed be an impossible reading. Rather, he is engaged precisely in ontology, but through transcendental epistemology.
Such a reconciliation of ontology and transcendental epistemology by means of the latter is, mutatis mutandis, precisely what I believe Plotinus is doing in V.1 and in many of his other so-called ‘ascents.’ He does not, pace Kant, see the mind and its necessary ways of intending being as somehow occluding some mind independent thing-in-itself. On the contrary, an analysis of mind or discursive reasoning, διάνοια, reveals that the conditions of mind knowing being include finite realities dependence on Intellect or νοῦς writ large. For it is Plotinus’s bold claim, one which ultimately derives from Plato, that mind can know τὸ ὄν if and only if there is some congruence between thinking and being, a congruence, in turn, grounded in a divine Mind. In other words, the explanation of being’s ordering to mind is its derivation from and constant dependency on Mind. Such is the full import of Parmenides’s famous dictum that “the same is the case for thinking and for being” (τὸ γὰρ αὐτὸ ἐστίν νοεῖν τε καὶ εἶναι).