(1) Who was Nietzsche quoting in this passage, and (2) what is it saying?

Question

This is a quotation from section 18 of First division: First and Last Things in Nietzsches Human, All Too Human:

When the history of the rise of thought comes to be written, a new light will be thrown on the following statement of a distinguished logician:-‘The primordial general law of the cognisant subject consists in the inner necessity of recognising every object in itself in its own nature, as a thing identical with itself, consequently self-existing and at bottom remaining ever the same and unchangeable: in short, in recognising everything as a substance.’

Who is he quoting from here, and what is it to say? It appears to be a statement of idealism to me, which would seem to contradict Nietzsches own thought, based on what he wrote in section 16.

Answer 1

Further to Mark Andrew's find on nochrisis.blog pointing to Denken & Wirklichkeit p.177, here is (1.) the purported original source, (2.) a Google translated version, (3.) the translated Nietzsche quote and (4.) the original Nietzsche quote from Menschliches, Allzumenschliches §18 (1878).

1. So sehr hat sich dem menschlichen Bewusstsein der Gedanke unbedingter, von dem Subjecte unabhängig existirender Gegenstände eingeprägt, dass der Begriff des Objects überhaupt mit dem des Unbedingten geradezu als identificirt oder verschmolzen erscheint. Nicht allein gewöhnlichen Leuten, sondern selbst philosophischen Männern ist dieser Begriff des Objects .am geläufigsten. Das lehrt uns die Geschichte der Philosophie. Das Bewusstsein , dass die Objecte des Erkennens von diesem letzteren selbst abhängig sind, [ist eine Erwerbung der neueren Zeit].

2. The idea of [unconditioned] objects existing independently of the subject has so impressed itself on human consciousness that the concept of the object in general appears to be identified or fused with that of the unconditioned. This concept of the object is most familiar not only to ordinary people, but even to philosophical men. The history of philosophy teaches us that. The consciousness that the objects of cognition depend on the latter themselves [is an acquisition of recent times].

3. The primordial general law of the cognisant subject consists in the inner necessity of recognising every object in itself in its own nature, as a thing identical with itself, consequently self-existing and at bottom remaining ever the same and unchangeable: in short, in recognising everything as a substance.

4. Das ursprüngliche allgemeine Gesetz des erkennenden Subjects besteht in der inneren Nothwendigkeit, jeden Gegenstand an sich, in seinem eigenen Wesen als einen mit sich selbst identischen, also selbstexistirenden und im Grunde stets gleichbleibenden und unwandelbaren, kurz als eine Substanz zu erkennen.

From the translation 2. we can see the general idea conveyed is that prior to "recent times" people thought that objects presented themselves in their complete, conditioned reality, but now we know that their conditioned objectivity depends on cognition. What we receive prior to meaningful cognition is the 'unconditioned' sense-reception of the object.

Although the gist of 2. and 3. are slightly similar the latter is at best a paraphrase of the former and it omits the distinction that an object's conditioned quality comes from cognition. Nevertheless this is the distinction that Nietzsche understands as the "new light" thrown on the matter, mostly courtesy of Kant.