352. Those who have averted themselves from thinking about the Divine when observing the wonderful things in nature, and who thereby become sensual, do not reflect that the sight of the eye is so gross as to see many little insects as an obscure speck, when yet each one of these is organized to feel and to move, and is accordingly furnished with fibers and vessels, also with a minute heart, pulmonary tubes, viscera, and brains; also that these organs are woven out of the purest substances in nature, their tissues corresponding to that somewhat of life by which their minutest parts are separately moved. When the sight of the eye is so gross that many such creatures, with innumerable particulars in each, appear to it as an obscure speck, and yet those who are sensual think and judge by that sight, it is clear how dulled their minds are, and therefore what thick darkness they are in concerning spiritual things.