If you put an ink bottle under a faucet and turn on the water, the ink will be replaced by clear water. If the ink bottle is a large one, it may take a while for the water to replace the ink. But by first pouring out the ink, you can fill the bottle with clear water quickly.
The first illustration gives a hint of one of Mrs. Eddy's statements in Science and Health: "The way to extract error from mortal mind is to pour in truth through flood-tides of Love. Christian perfection is won on no other basis."Science and Health, p. 201 The second illustration might point to another statement of hers about self-correction: "What renders both sin and sickness difficult of cure is, that the human mind is the sinner, disinclined to self-correction, and believing that the body can be sick independently of mortal mind and that the divine Mind has no jurisdiction over the body." Science and Health, p. 218
Through self-correction the human mind empties itself of false beliefs and becomes ready to accept spiritual truths. Although spiritual truths will always be the victor, as long as false beliefs are harbored the victory is delayed. The human mind has a tendency to hold on to material beliefs that evil, the unlikeness of infinite God, good, can be real; that man, the loved child of a perfect Father, can be a victim of evil, or error; and that error can overpower Truth. It is disinclined to give up the illusion that life is material, and very slow to accept that man is spiritual.