Kant rightly maintains that the admixture of egoistic motives beclouds the purity of the disposition, and consequently diminishes its moral worth.

The mouse-bat peers; the stealthy vole Creeps from the covert of its hole; A shimmering moth its pinions furls, Grey in the moonshine of his curls; 'Neath the faint stars the night-airs stray, Scattering the fragrance of the may; And with each stirring of the bough Shadow beclouds his childlike brow.