An old saying

Each war...... and quicker throb of the heart wears so much of life away. 

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The passions, the affections are not to be indulged in by him who seeks to know.
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For they wear out the earthly body with their own secret power.
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And he who would gain his aim---------must be cold !

He must not even desire too earnestly or too passionately the object he would reach.
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Else, the very wish will prevent the possibility of its fulfilment, at best  
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Retard or throw it back.