The Frankfurt School developed Critical Theory, which essentially contrasts the divergence of reality from its ideals.

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In a masterly introduction, Mr Rose suggests that recent developments in cultural and critical theory have obscured, or more accurately ignored, the experience of working-class audiences of books, plays and paintings.

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Given that many philosophers saw critical theory as a way for English professors to do philosophy really badly, it should not come as a surprise to find that some with a keen understanding of neuroscience are deeply skeptical of this attempt to say something new about old books.

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By 1990, liberal Harvard Law School was torn apart by a left-wing theory called critical legal studies, which condemned the American legal and economic system as .

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Traditionally, brand was essentially viewed as a communication and fundraising tool, but we found that a new paradigm was emerging where brand was increasingly being considered in a strategic way, fundamentally anchored in the mission and values of an organization and critical at every step in the theory of change of an organization.

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At Remedy Health Media, a health information and technology company just outside Washington, social media manager Stuart Perkins has another theory about why play is critical.

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The combination of cheap jets with greater fuel efficiency and a critical mass of these critters in the sky can, in theory, lower the price per seat considerably.

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And systems and complexity theory suggest strongly that a relatively small number is in play when it comes to the size of the critical mass of folks in whom lost confidence can have sweeping, cascading effects.

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