"The experience of Joy for C.S. Lewis was the precursor to an intellectual and moral conversion which culminated in his acceptance first of theism, then full blooded Christianity. Almost from the moment of his conversion to Christianity, Lewis’ life exploded with creativity and prodigious accomplishment. His achievements would not have been possible without his experience of sehnsucht—that intense nostalgia for something lost which had to be found. This sense that fulfillment comes from the recovery or remembrance of things past is at the heart of conservatism, and echoes the wisdom of Plato who taught that all learning was a matter of remembering what we once knew."
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This makes me realise how I am not yet converted.