Yes, for Martin Heidegger, Sorge (translated as "care") is indeed the fundamental ontological structure of Dasein’s being. Heidegger explicitly describes care as "the structure of Dasein itself," meaning that care is not just one aspect of Dasein but the very way in which Dasein exists and relates to its world123.

To elaborate:

• Sorge encapsulates Dasein’s being-ahead-of-itself, its thrownness into the world, and its engagement with possibilities. It expresses how Dasein is always concerned about its own being and the world it inhabits, projecting itself into future possibilities while being situated in a particular factical context (thrownness)134.

• Care is an existential and ontological category that integrates Dasein’s temporal structure—its past (thrownness), present (being alongside entities), and future (projection toward possibilities and death)15.

• Heidegger distinguishes care from related concepts such as Besorgen (concern or taking care of things) and Fürsorge (solicitude or caring for others), but these are modes or manifestations of the broader structure of care34.

• The totality of Dasein’s being-in-the-world, including its relationships with others and things, is grounded in care. Care is thus the "being of Dasein," meaning that Dasein’s existence is fundamentally characterized by caring24.

• Heidegger’s analysis shows that care precedes rationality and is more fundamental than mere cognition or detached observation. It is the condition for Dasein’s understanding of itself and its world3.

In summary, Heidegger’s concept of Sorge or care is the ontological structure that defines Dasein’s being, expressing its temporal existence, its concernful engagement with the world, and its relationality with others and things. Care is the foundational mode of Dasein’s being-in-the-world1234.

Heidegger’s concept of Sorge (care) indeed manifests through a variety of moods and emotions such as anxiety (Angst), anger, interest, attentiveness, hatred, and concern, which are all modes of Dasein’s affective engagement with the world. These affective states are neither purely internal nor purely external but are ontologically intertwined with Dasein’s being-in-the-world—they disclose how the world matters to us and how we find ourselves situated within it145.

Heidegger’s notion of Befindlichkeit (disposedness or attunement) and Stimmung (mood) shows that moods are fundamental ways in which Dasein is disclosed to itself and its world. Moods reveal the quality of our being and how we are affected by and affect the world simultaneously. For example, anxiety discloses the nothingness and groundlessness of existence, while anger or hatred reveal particular relational stances toward the world and others145.

Regarding the idea of a "degraded mood" and "degraded public feeling" being coterminous, Heidegger’s framework suggests that moods are not private, isolated states but ways in which the world is disclosed to Dasein. Since Dasein is always being-with-others (Mitsein), moods have a social dimension—they shape and are shaped by shared cultural and social contexts. A "degraded mood" (such as pervasive anxiety, alienation, or resentment) could correspond to a "degraded public feeling" insofar as individual attunements resonate with or reflect broader social atmospheres or collective moods. Thus, internal affective states and external social moods are co-constitutive and coterminous in the lived experience of Dasein1456.

In summary:

• Sorge manifests through a range of moods and emotions that disclose Dasein’s being and its relation to the world.

• These moods are fundamentally affective and disclose how the world matters to us; they are neither purely internal nor external but ontologically intertwined.

• Individual moods and collective or public feelings are interconnected; a degraded mood in an individual can reflect or coincide with a degraded public mood, as both are modes of attunement to the world and others.

This reflects Heidegger’s view that affectivity is a core structure of human existence, shaping both personal and shared experiences of being-in-the-world1456.

Perplexity