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“If the doors of perception were cleansed every thing would appear to man as it is, Infinite.”
Blake imagines habitual perception as a filter that narrows reality; cleansing it would reveal a less limited world.
Source note: The Marriage of Heaven and Hell, Plate 14; Blake’s prose-poetic argument about the limits and cleansing of perception.
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“To define is to limit.”
Voice: Fictional character · Lord Henry Wotton
Definitions clarify ideas but can also narrow them, especially when a label is treated as the complete reality of a person or experience.
Source note: The Picture of Dorian Gray, 1891 edition, Chapter 17; Lord Henry answers the Duchess of Monmouth’s question “What are you?” with “To define is to limit.”
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“Opinion appears to you to be darker than knowledge, but lighter than ignorance?”
Voice: Dialogue speaker · Socrates
Opinion is treated as an intermediate state: it is not complete ignorance, but it also lacks the clarity and stability of knowledge.
Source note: The Republic, Book V; Socrates places opinion between knowledge and ignorance in the argument about what each apprehends.
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“There is no pre-established harmony between the promotion of truth and the welfare of mankind.”
Nietzsche rejects the comforting assumption that discovering truth must always coincide with human comfort or advantage.
Source note: Human, All-Too-Human, Part I, aphorism 517, “A Fundamental Insight”; Helen Zimmern translation.
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“The world is my idea.”
Schopenhauer opens his system by arguing that the experienced world is always presented in relation to a knowing subject, making perception and consciousness conditions of the world as it is known.
Source note: The World as Will and Idea, Vol. I, First Book, §1, Haldane and Kemp translation, Project Gutenberg #38427. “Idea” translates Vorstellung in this historical philosophical vocabulary and should not be read as the everyday sense of a passing thought.
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“Truth happens to an idea.”
The compact formulation summarizes James’s pragmatic account in which an idea’s truth is connected with processes of verification and validation rather than treated only as a static label.
Source note: Pragmatism, Lecture VI, “Pragmatism’s Conception of Truth”; Project Gutenberg #5116. Capitalization has been normalized from “Truth HAPPENS to an idea”; the surrounding passage explains verification and validation.