changeability of nature. It is, first and foremost, a system of formal rules that scientists use to “decipher the book of nature,” as Galileo understood it;50 and under which fluctuations are read as departures from a fixed norm. Using these formal rules, scientists order and systematize finite individual experiences of nature into a standardized manifold that is impossible to find in the world of our living. As Alexandre Koyré notes: “The Galilean concept of motion (as well as that of space) seems to us so ‘natural’ that we even believe we have derived it from experience and observation, though, obviously, nobody has ever encountered an inertia motion for the simple reason that such a motion is utterly and absolutely impossible.”51
This is what Husserl reminds us: formal judgments are the foundation from which a scientific method proceeds to assemble, categorize, and “order” disparate empirical claims into a system that we call science. Everyone practicing science must become a master of these formal rules, which can be repeated across time and space. They express truth in itself. Truth is possible only in the formal domain, unaffected by changeable experience; whereas natural laws are hypothetical, expressed in abstract, simplified forms that contain many singular instances as their constituent parts and that explain those parts according to a type. Truth is the ideal limit, which, in the empirical domain, we can approach only asymptotically (LI, § 6, 18).
In order to communicate scientific hypotheses about nature, there must be a system of formal rules that is understandable across time and space. As Husserl puts it: “Every operative fashioning of one form out of others has its law [. . .] of reiteration,” which makes possible “the infinity of possible forms of judgments” (FTL, § 13, 52–53; italics in original). Otherwise, there would be nothing from which science could proceed and make its prognostications. To simplify somewhat, by taking as an example the simple formal judgment “S is p,” we can say that if this predicative judgment did not apply to countless empirical instantiations of predication in nature, which are changeable by definition, we could not have science. Originally, this predication was nothing but extrapolation from repeated regularities in nature. Once the repeatability of events can be expressed by the formal structure, for example, “S is p,” this formal proposition—stripped of particularities we encounter in our everyday living—will order our future experience.52
From then on, we can use the formal predicative proposition, that is, the formal type that covers any thing whatsoever in order to understand a particular “thing” in nature. In the case of the formal assertion “S is p,” we substitute any objects whatsoever for S and p, and the resulting judgment is considered valid, irrespective of our experience, because of its “indwelling” form. So, by applying this form to our experience and by substituting our empirical observations for S and p, the statement “A swan is white,” for example, becomes an empirical instantiation of this basic predicative form; because we know that this formal, or experientially empty, apophansis is a form that embraces many particular instances of objects experienced by us. This form, once established, is given to us a priori; we can access it by insight alone. It gives us the empty form of predication that applies to any object whatsoever. Once we use it to judge our experience, it holds as long as we do not encounter, for example, a black swan. Once encountered, although the form is unaffected by this discovery, its empirical correlative—the act of judgment—is changed. The basic form of a predication, S is p, does not cover this new empirical fact. One has to use a different formal judgment in order to assert, perhaps a disjunctive proposition that “S is either p or r”—“A swan is either white or black.”
In the empirical domain, “in the vast majority of cases we lack [. . .] absolute knowledge of truth, in whose place we make use [. . .] of the inner evidence for a higher or lower degree of probability for our state of affairs, with which, if probability-levels become high enough, a firm judgement is usually associated” (LI, § 6, 17). If knowledge is tied to truth, then it becomes clear that truth is nothing but the idea that will guide our search for knowledge (LI, § 6, 18).53
Hence, as Husserl stresses, the claim that “as far as their theoretical content is concerned [, . . .] logic is related to psychology just as any branch of chemical technology is related to chemistry, [or] as land-surveying is to geometry etc.[,]” is absurd (LI, § 17, 40).54 It is, rather, the other way around: logic is the foundation that supplies the formal laws of judgment to sciences that deal with the empirical world,55 in the same way that geometry, although originally derived from land-surveying, now grounds it.
It is worth underscoring Husserl’s critique of causal justification of formal laws of logic in the manner of natural laws. To highlight the mistake of attributing to hypothetical natural laws the status of formal apodictic laws, he cites Lipps again:
The rules, therefore, on which one must proceed in order to think rightly, are merely rules on which one must proceed in order to think as the nature of thought, its specific lawfulness, demands. They are, in short, identical with the natural laws of thinking itself. Logic is a physics of thinking or it is nothing at all.56
As already noted, Husserl is critical of Lipps, who explains logic as being determined by our psychological makeup. As Husserl says, in the claim just cited, Lipps already uses the formal law of causation—the specific lawfulness of thinking—to explain his assertion about “the nature of thought.” Our judgment that one event proceeds from another already presupposes the formal law of causation. It is not the case that the rules of our thinking are the thinking itself. To put it differently, this is the metabasis, pointed out by Husserl, that erroneously reduces the rules of thinking to the thinking itself.
The case of the archaic Greeks might serve as an explanation. Fire, for example, can be explained by recourse to myth: “One day someone went into the forest and was given a burning log by one of the gods.” Fire is then explained by mythical powers and there is no need to look for other justification. Myth provides all: “cause,” “effect,” and “reasons” in one package; the story that is told. Everything is as it always was.57 The idea of reasoning in the form of validation—that is, providing reasons for our assertions—is antithetic to mythical thinking.
For the ancient philosophers, the mythical explanation was “unscientific.” Likewise, in our time, to assert something means that we also give reasons, so that it can be seen why something is the case or why it is not. Without justification presented in the form of reasoning, there is no recourse to an understanding that others can follow. Why should they believe our claims? So we give reasons as to why there is fire: yet, in offering reasons for fire, we already presuppose the principle of causality; that is, the formal law that every consequent has its antecedent, which explains it. Or, more simply, the notion that every cause has its effect, and that we can understand certain events according to those that preceded them.
Plato considered “why” something is or is not when he recounted Socrates’ explanation to Phaedo: “When I was a young man I was wonderfully keen on that wisdom which they call natural science, for I thought splendid to know the causes of everything, why it comes to be, why it perishes and why it exists.”58 However, Aristotle was the first to formalize this line of thinking. From our empirical encounters with the world, Aristotle abstracted the four formal causes that became the basis for our understanding. His four causes were derived from the experience of things that the Greeks encountered in their everyday living,59 and they referred back to it.60 In other words, the four causes explained experience a priori.
After Aristotle, to understand things in the world is to search for the four causes: material, formal, efficient, and final. Without knowing these causes, we cannot claim to know the existence and nature of the thing. By searching for causes, we are looking for a “why” in terms of antecedents. Senses—that is, experience—as Aristotle explains, “do not tell the ‘why’ of anything—e.g. why fire is hot; they only say that it is hot.”61 To not ask why is to not seek a cause. (Gods gave us fire: there is nothing more to it.) By contrast, we search for causes to understand why something comes onto being; as Plato says, “why it perishes and why