According to Plato’s “Theory of Forms,” the physical manifestation of a form can never be as perfect as the idea. In other words (i.e. found on Wikipedia because it’s a Saturday and I’m not digging through my old philosophy books and notes for this):
For Plato, forms, such as beauty, are more real than any objects that imitate them. Though the forms are timeless and unchanging, physical things are in a constant change of existence. Where forms are unqualified perfection, physical things are qualified and conditioned.
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A Form is aspatial (transcendent to space) and atemporal (transcendent to time).