day no. 15,724: good lost and evil got

Greedily she ingorg'd without restraint,
And knew not eating Death: Satiate at length,
And hight'nd as with Wine, jocond and boon,
Thus to her self she pleasingly began.

O Sovran, vertuous, precious of all Trees
In Paradise, of operation blest
To Sapience, hitherto obscur'd, infam'd,
And thy fair Fruit let hang
-- John Milton, Paradise Lost

Sapience is a word for wisdom that derives its meaning from a word associated with tasting and in French can even mean, "having good taste." Here, Milton cleverly asserts it into the story at a point where the tasting the fruit from the Tree of the Knowledge of Good and Evil was likened by the serpent to obtaining wisdom. But what they gained in grabbing that fruit, while new, was not wisdom. In other words, Satan can make sin look tasty, but he cannot make it less poisonous.

O Eve, in evil hour thou didst give eare
To that false Worm, of whomsoever taught
To counterfet Mans voice, true in our Fall,
False in our promis'd Rising; since our Eyes
Op'nd we find indeed, and find we know
Both Good and Evil, Good lost, and Evil got
-- John Milton, Paradise Lost

The tasting of the fruit led to new knowledge of good and evil; good lost and evil got. They did not know the presence of evil before and they had never misplaced good. Now, as a result of eating the forbidden fruit, they gained a new knowledge of good and evil. They would now know good only from afar and evil only to well from within. This gain incarnates well the sentiment, "subtraction by addition."