Radical Ontic Structural Realism (ROSR) is a metaphysical position in the philosophy of science asserting that structure is all that exists, and objects or individuals are metaphysically eliminable. [1, 2, 3]

Core Ideas

Elimination of Objects: Unlike moderate structural realism—which allows for "thin" objects or items that only possess relational properties—ROSR claims there are no fundamental things, particles, or individuals at the base of reality, only free-standing relations. [1, 2, 3, 4]
Relations Without Relata: ROSR famously argues for "relations without relata", meaning the web of physical or mathematical structure exists independently of any things being related. [1, 2, 3]
Structuralist Existence Monism: Recent reformulations (such as Aiden Meyer's work) reframe ROSR through Spinozist monism, where the entire universe is viewed as a single, foundational world-structure, and everyday perceived "objects" are treated merely as modes or states of that structure. [1, 2]

Key Objections

The "Relations Require Relata" Charge: Critics argue it is conceptually incoherent to have a relation if there is nothing being related. Proponents often respond that "it’s relations all the way down," or that higher-level relational structures substitute for traditional objects. [1, 2, 3]
Account of Plurality: Critics question how an object-free, purely relational cosmos can account for the distinct, everyday plurality of medium-sized dry-goods (like tables, chairs, and individual people) that we experience. [1, 2]

If you'd like, I can:

• Contrast Radical Ontic Structural Realism with Moderate Ontic Structural Realism
• Explain how quantum field theory or spacetime state realism is used to defend ROSR

Phenomenological realism is a philosophical position that rejects Edmund Husserl’s later transcendental idealism in favor of the view that the objects of consciousness exist independently of the mind that perceives them. [1, 2]

Core Concepts

Independence of Reality: Unlike transcendental idealism—which holds that objects are constituted by or dependent on consciousness (noemata)—phenomenological realism maintains that the noumenon (the thing-in-itself) exists objectively and independently of human awareness. [1]
Back to the Things Themselves: Proponents took Husserl’s early motto ("zu den Sachen selbst") literally, arguing that we can directly know the real essences and existence of things rather than just phenomena inside consciousness. [1]
The Munich and Göttingen Schools: Early students of Theodor Lipps (such as Adolf Reinach, Johannes Pfänder, Max Scheler, and Roman Ingarden) split from Husserl after he adopted an idealist framework in Ideas I (1913), forming the core of realist phenomenology. [1, 2]

Key Figures

Adolf Reinach: Applied realist phenomenology to the a priori foundations of civil law and developed theories of social acts.
Max Scheler: Pioneered a material value-ethics based on the objective, independent existence of moral values.
Hedwig Conrad-Martius: Explored the ontology of real beings, nature, and the self as a central voice in early realist circles.
Josef Seifert: Modern champion of the tradition who explicitly advocates a return to knowing the "thing-in-itself". [1, 2, 3, 4]

Would you like to explore how phenomenological realism differs specifically from Husserl's transcendental idealism, or look into the work of a particular figure like Max Scheler or Adolf Reinach?