There is wisdom in Hugo of St. Victor, in his advice: love is the eye. Love sorts things out; it makes for the higher synthesis. It was this insight that also prompted St. Augustine to write: Love and do as you like.
But the last word on this should go to Jesus. He also taught a class on hermeneutics, the Beatitudes. Among other things, he said this: Happy are the pure of heart; they shall see God.
For him, purity of heart and poverty of spirit are what clear the eyesight and enable us to see straight. Conversely, all sin, selfishness, and greed weaken our eyesight because, through that prism, we see a world that is as self-centered, cynical, untrustworthy, and hardened as we are.
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