edge: Cognitio is clara, distincta, adaequata, and intuitiva [clear, distinct, adequate, and intuitive]. Leibniz emphasizes that if an act of knowledge is simul adaequata et intuitiva [at one and the same time adequate and intuitive], then it is perfectissima [most perfect]. Thus, intuitive knowledge is the most perfect. In order to formulate this characteristic of knowledge as Leibniz understands it, I will list in rough fashion, the four properties he mentions without going into any special interpretation at this point.
1. According to Leibniz, an act of knowledge is clear when I have the thing to be known in a certain way, that is: cum habeo unde rem re-praesentatam agnoscere possim: when I have the thing that is mentally intended,99 in such a way that I can recognize the what-is-intended in and of itself, i.e., when I bring-present to myself the thing that I meant, in such a way that I can identity what-I-meant with that thing. Therefore, what constitutes the character of clarity and what makes knowledge clear is the possibility of re-cognition of the thing, the possibility of [the] identity [of what-I-intend] with the thing itself. And  if I want to prove that an act of knowledge is clear, I must take that act of knowledge, and duco in rem praesentem, “I lead it to the thing that is present.” In other words, I must make present to myself the very thing I intend.
2. An act of knowledge is distinct when, briefly put, I have a nominal definition of it—in Leibniz’ words, a definitio nominalis. By that Leib-niz means the enumeratio notarum sufficientium, the enumeration of the determinations of the thing that are sufficient to distinguish it from other things and to determine it as this thing—thus, the enu-merability of adequate characteristics. And then Leibniz says there is also distinct, clear knowledge of things that are undefinable, that have no nominal definition—namely concepts, which are notiones primitivae [primitive notions]—there is also clear knowledge of a simple concept. That is, the simple concept is nota sui ipsius: it is the distinguishing mark of itself; it simply presents itself. It is not reduc-ible to other determinations, caret requisitis: it lacks determination by means of another. It is given by means of itself.
3. Leibniz characterizes knowledge as adequate—cum vero id omne quod notitiam distinctam ingreditur, rursus distincte cognitum est. An act of
99. [Misread in GA 21 (p. 118.29) as representatem; cf. Moser, p. 250.6–7.]