one's more permanent and positive generalisations. It puts what one notices above what one knows. It means the monstrous heresy that seeing is believing. A white cow at one particular instant of the evening light may be gold on one side and violet on the other. The whole point of Impressionism is to say that she really is a gold and violet cow. The whole point of Impressionism is to say that there is no white cow at all. What can we tell, it cries, beyond what we can see? But the essence of Mysticism is to insist that there is a white cow, however veiled with shadow or painted with sunset gold. Blessed are they who have seen the violet cow and who yet believe in the white one. To the mystic a white cow has a sort of solid whiteness, as if the cow were made out of frozen milk. To him a white horse has a solid whiteness as if he were cut out of the firm English chalk, like the White Horse in the valley of King Alfred. The cow's whiteness is more important than anything except her cowishness. If Blake had ever introduced a white cow into one of his pictures, there would at least have been no doubt about either of those two
