Summary: Ideas for a Pure Phenomenology and Phenomenological Philosophy

In Ideas for a Pure Phenomenology, Husserl aims to define phenomenology—the science of phenomena—in contrast to psychology, which consists of immanent descriptions concerned with psychic experience and confined to inner experience.

Phenomenology stands as far apart from psychology as geometry does from a natural science such as physics, even though both share the same object: consciousness.

Whereas psychology deals with facts and natural realities, phenomenology, as an "eidetic" science, concerns itself with essences, that is, with unreal phenomena.

It requires abandoning the natural attitude through phenomenological reduction (or eidetic reduction). To clarify how this abandonment occurs and to define more precisely the meaning of this reduction, Husserl begins from the natural point of view—that is, from consciousness as it presents itself in psychological experience, in opposition to the world.

Section I: Essences and the Knowledge of Essences

The natural attitude starts with experience and remains within it. The horizon that defines its domain of inquiry is the world. The natural attitude equates being true, being real, and being in the world.

Every science is grounded in an originary intuition. For the natural attitude, this intuition is perception. In this sense, the world is defined as the totality of objects of possible experience ¹.

The sciences derived from natural experience are those that engage with the world. These include the natural sciences (physics, biology, etc.) as well as the sciences of the mind (sociology, psychology, etc.).

Facts are contingent; they could be otherwise. That tree over there might not exist or might exist elsewhere. Husserl calls the object of the sciences derived from the natural attitude "facticity," which is always characterised by contingency.

Yet each thing, despite its contingency, has an essence—an Eidos—which must be grasped in its purity and which, in turn, is governed by essential truths ².

This Eidos is apprehended when we recognise that an individual object is not merely something singular, a "this there"; rather, because of its particular constitution, it possesses its own specificity—its permanent bundle of essential predicates that necessarily follow from what it is ³.

Husserl illustrates this with the example of music: each sonority has its essence, and at the highest level, we find the general essence of sound.

Empirical intuition of the individual can be transformed into a vision of essence, or ideation. The object of this vision is the corresponding pure essence, or Eidos.

This vision, which discloses essence, may be either adequate or inadequate.

Husserl thus distinguishes, in Ideas for a Pure Phenomenology, between sensible intuition and eidetic intuition: through the latter, we must grasp the essence concealed at the heart of the object that we first glimpse through sensible intuition.

He defines the object, like the logician, as any possible subject of true predicative judgments ⁴ and refrains from attributing to the eidos or essence the mystical meaning found, for example, in Plato.

These two types of objects—existing real facts and their essences—give rise to truths that belong to two distinct planes:

Truths about essences do not contain the slightest assertion about facts. Nor can any truth concerning facts be derived from them alone ⁵.

The essence of an object can be likened to a genus: The essence—the genus of colour—is distinct from the essence—the genus of sound ⁶. Thus, any judgment about essences can be equivalently reformulated as a judgment of unconditioned generality ⁷.

Opposed to the sciences of fact (as we have seen: physics, psychology, etc.) are the sciences of essence: logic, pure mathematics, the pure theory of time and space, etc.

¹ Idées directrices pour une phénoménologie, Gallimard, Paris, 1950, trad. P. Ricoeur, §1, p.15
² §2, p.17
³ ibid.
⁴ §3, p.22
⁵ §4, p.25
⁶ §5, p.27
⁷ §5, p.28