Nog hooguit één keer wellicht haal ik een tekst naar dit dossier en dan hoop ik zover te zijn om met mijn interpretatie te komen van de aan de orde gestelde kwestie, zoals ik die in dit blog formuleerde: n.l. om de vraag hoe het voorbeeld dat Spinoza behandelt in 1/17s gelezen moet worden, wat de rol ervan is in het betoog en of het spreken over gemeenschappelijke essentie van mensen, die dan ook nog ‘een eeuwige waarheid’ wordt genoemd, door Spinoza zo gemeend is: of het zijn eigen opvatting weergeeft of dat hij – bij wijze van argument – even meegaat met die gedachten die hij tenslotte verwerpt. Daar kom ik nu spoedig op, naar ik verwacht.
Op zaterdag 30 september 2017 had ik het blog: “Volgens Michael A Istvan Jr. is Spinoza een realist in de variant van universalist,” waarin ik verwees naar diens omvangrijke proefschrift, waarin hij zeer veel literatuur behandelt, waarbij hij juist op zoek is naar hoe in de secundaire Spinoza-literatuur het essentiebegrip wordt behandeld in het licht van de aloude onderscheid tussen realisme en nominalisme: waarbij hij de aloud posities nog verder onderscheidt (ik nam het schema ervan over in dat blog).
In zijn § 6.3 1p17s die loopt van p. 201 – 226, gaat hij uitgebreid in op 1/17s (26 bladzijden!). Daaruit haal ik een boeiend onderdeel dat juist voor onze discussie hier van belang is. Ik raad lezing van de hele paragraaf aan [de dissertatie heb ik ook nog niet in z’n geheel gelezen]. Ik citeer de tekst met de nummering van zijn voetnoten, waarvan ik hier eindnoten maak, maar voor de verwijzing naar de bibliografie verwijs ik naar zijn dissertatie [PDF].
Third, in a comment to her Italian translation of Ethics, Giancotti Boscherini follows Koyré in suggesting that Spinoza is not speaking in his own voice, only rhetorically, on various matters in 1p17s. That is how, for example, she explains away the apparent tension, originally pointed out by Tschirnhaus (Ep. 63 IV/275), between the following two Spinozistic principles when it comes to God as cause of his effects: Letter 4’s causal similarity principle, a principle according to which the effect has in common with the cause what it receives from the cause (see also 1a5 plus 1p3, 4pref II/208/5-6, 5a2; KV 2.24 I/104/25-29, KV app1a5 I/114/15; TTP 4 III/58/19-20), and 1p17s’s causal dissimilarity principle, a principle according to which the effect differs from the cause precisely in what it receives from the cause (see Chapter X). Giancotti Boscherini says that Spinoza was appealing to the dissimilarity principle not because he believed it but in order to illustrate the extreme position, and one that many take Spinoza personally to deny, that the intellect of God is entirely other to the intellect of man. Since Spinoza brings up the issue of men sharing an essence as an example of the dissimilarity principle that, according to Giancotti Boscherini, he did not really believe, perhaps the men sharing an essence should itself be suspected as not being Spinoza’s true view. The take home point would be this. 1p17s is largely a reductio against the view that God in his absolute nature has intellect. The common essence passage is one of the unacceptable results of this false view that God has intellect. Man having a common essence is, for Spinoza, one of the absurd consequences of the view that God has intellect.
Fourth, the defender of the antirealist interpretation could always stress how the 1p17s passage is just some passing remark buried in a scholium. This is significant because scholia, lacking the formal geometrical trappings of other areas, are presumably where Spinoza permits himself to speak comparatively loosely, unencumbered by that “cumbersome Geometric order” where clarity is a first and foremost priority (4p18s and TTP 7.17). So the idea would be that, since Spinoza is supposed to be an antirealist, we should disregard the realist 1p17s passage.
I am one who finds it incumbent on the commentator to make every effort to see how all the words of an author harmonize (from scholia to propositions, from letters and notes to published works). So my default assumption—at least when I bracket off Giancotti Boscherini’s line of reasoning, which I do not find convincing anyway (see Chapter X)—is that Spinoza must just be thinking of essence in a different way in those passages that apparently conflict with 1p17s. Only the most uncharitable interpreters would hold up 1p17s and 2d2 next to each other and declare: contradiction! This is especially the case in light of the following fact. Contrary to what several Spinoza scholars seem to think, an individual’s having its own peculiar essence is, as Aristotle among so many others have maintained (and as is simply true by the light of reason), compatible with that individual instantiating one and the same essence as some other individual. On the one hand, Peter and Paul could have one and the same “human nature in general,” to use Spinoza’s words (1p8s2 II/51/5), that is, an essence exclusive of the peculiarities about each (the peculiarities grounding their actually being two). That would be the sort of essence in discussion at 1p17s (see TP 2.2). On the other hand, each could have his own peculiar essence, an essence constituted by the totality of his features and so including the ones peculiar to him as well as the ones that he has in common with the other man. That sounds more like what Spinoza calls the “actual essence” at 3p7. After all, the actual essence of an individual is just the sum of its power (3p7d) and, since everything in Spinoza’s ontology has power or efficacy (1p36, 1p36d), the conception of its total power must involve the conception of the totality of its features. So I would say that the essences had by multiple individuals are the non-singularizing essences, if you will, of those individuals. And I would say that the essences that uniquely pick out one individual from all the rest are the singularizing essences, if you will, of those individuals. 2d2 would concern the singularizing essences whereas 1p17s (and certain passages that I will bring up in this chapter) concern non-singularizing essences.
In the end, I find the above reasons for striking 1p17s from the record to be weak. But if only for the sake of the argument, I will strike the passage from the record (at least temporarily).
 Giancotti Boscherini 1988.
 Koyré 1950.
 See the following few commentators who have mentioned this pressing tension in Spinoza’s thought: Di Poppa 2006, 273ff; Rivaud 1906, 128-130; Schmaltz 2000, 86; Curley 1985, 427n51; Deleuze 1992, 48, 356n11, 356n12; Gueroult 1968, 286-295; Giancotti Boscherini 1988; Lachièze-Rey 1950, 156-159.
 See also Manning 2012, n8.
 See Daniel 2013a, 40.
 See Della Rocca 1996, 87, 187n13; Della Rocca 2004; Jaquet 2005, 85.
 Martineau 1882, 150n2, 111; Rice 1991, 300n39; Hampshire 1988, 108; see Melamed 2013d, 58n194.
 See Aristotle Metaphysics, 1003a14-14 and 1035b28ff.
 See Della Rocca 2008, 95; Soyarslan 2013.