"Blue is one object of sensation and green is another, and consciousness, which both sensations have in common, is different from either." Present an account of Moore's refutation of idealism with reference to this statement.

Understanding British Idealism and its Core Tenets

British Idealism, influenced by German philosophers like Kant and Hegel, contended that reality is not independent of mind. Key figures such as T.H. Green, F.H. Bradley, and Bernard Bosanquet argued for a holistic view of the universe, often conceiving of it as a single, all-encompassing spiritual or mental reality known as the Absolute. They rejected atomistic empiricism and the idea of external relations, advocating instead for a coherence theory of truth.

• Mind-Dependence of Reality: The central tenet was that physical objects and their qualities exist only insofar as they are perceived or thought.
• Rejection of Empiricism: Idealists criticized the empiricist notion that knowledge originates solely from sensory experience of an external world.
• The Absolute: Reality was often understood as a unified, coherent system, an Absolute that integrates all phenomena.

Moore's Philosophical Stance: Common Sense Realism

G.E. Moore, in stark contrast to the idealists he initially engaged with, championed a "common sense" realist position. He argued that our ordinary, everyday beliefs about the world are largely true and known with certainty. His work, particularly "A Defence of Common Sense" (1925), affirmed the existence of an external world and our direct knowledge of it, challenging both idealism and skepticism.

• Defense of Common Sense: Moore believed that fundamental common-sense propositions, such as the existence of one's own body and other people, are indisputably true.
• Critique of Idealism: He viewed idealist arguments as undermining these obvious truths, often by conflating distinct concepts.

Moore's Refutation of Idealism: Disentangling Sensation and Object

Moore's "Refutation of Idealism" directly targets the idealist's premise that "to be is to be perceived" (esse est percipi). The core of his argument, as encapsulated in the statement, "Blue is one object of sensation and green is another, and consciousness, which both sensations have in common, is different from either," lies in demonstrating a crucial distinction that idealists allegedly overlook or conflate.

The Idealist's Conflation

Idealists, according to Moore, often treat a sensation (e.g., the sensation of blue) as if it were identical to its object (the quality blue itself). They believe that for "blue" to exist is simply for someone to have a sensation of "blue." Moore argues this identification is a fundamental error, leading to self-contradiction.

Moore's Distinction: Consciousness vs. Object

Moore meticulously breaks down any given sensation into two distinct elements:

• Consciousness (the mental act): This is the act of being aware or perceiving. It is the subjective, mental event common to all sensations. When we experience "blue" or "green," the act of "sensing" or "being conscious" is a shared element.
• The Object of Sensation (the quality perceived): This refers to the specific quality itself, such as "blue" or "green." Moore asserts that these qualities are distinct from the consciousness of them.

The quoted statement highlights this separation: "Blue is one object of sensation and green is another, and consciousness, which both sensations have in common, is different from either." This implies:

1. The quality 'blue' is distinct from the quality 'green'.
2. The mental act of 'consciousness' is present in both the sensation of blue and the sensation of green.
3. Crucially, this 'consciousness' itself is distinct from 'blue' and 'green' as qualities. Consciousness is diaphanous; it is transparent, an act of awareness *of* something, rather than being that something itself.

To illustrate, when one has a "sensation of blue," Moore argues that the sensation is not itself blue. If it were, the sensation of blue would literally possess the property of blueness, which is nonsensical. Similarly, the act of seeing a color is an awareness where the color itself exists as an object outside of that awareness.

Undermining "Esse Est Percipi"

By establishing this clear distinction between the act of perceiving (consciousness) and the object perceived (the quality like blue or green), Moore directly challenges the idealist's foundational principle:

• If "blue" were identical to the sensation of "blue," then "blue" would cease to exist the moment the sensation ceased.
• However, if "blue" is an object distinct from the sensation/consciousness of it, then its existence is not necessarily dependent on being perceived. The quality "blue" can exist independently of someone being conscious of it.

Moore contended that idealists confuse a 'sensation of blue' with 'blue' itself. He argued that it is a 'self-contradictory error' to identify a part (blue) with the whole (sensation of blue) or with the other part (consciousness) of the same whole. This analytical separation demonstrates that the object of sensation is not a mere "content" of the mind, but rather an independent entity.

Moore’s refutation does not aim to prove the falsity of the idealist thesis that reality is spiritual. Rather, he intends to show that the arguments idealists put forth, particularly those based on "esse est percipi," are logically flawed and lead to contradictions due to their failure to distinguish between the mental act of awareness and the non-mental object of that awareness.

Aspect	Idealist View (Critiqued by Moore)	Moore's Refutation
Sensation and Object	Sensation and its object (e.g., "sensation of blue" and "blue") are often conflated or considered inseparable. To exist is to be perceived.	Distinct elements: consciousness (the mental act) and the object (the quality itself). The object exists independently of being perceived.
Existence of Qualities	Qualities like "blue" are mind-dependent; they are contents of consciousness and cease to exist when not perceived.	Qualities like "blue" are mind-independent; they are objects *of* consciousness, not identical *with* consciousness, and can exist unperceived.
Nature of Consciousness	Consciousness is a container or content-holder for objects/qualities.	Consciousness is a 'diaphanous' act of awareness, transparent, pointing beyond itself to its object.
Metaphysical Conclusion	Reality is spiritual/mental (Idealism).	Idealist arguments for mind-dependence are flawed; opens the door for realism where an external world exists independently.