The considerations for changing abstract method declarations in interfaces are the
same as those for abstract methods in classes, as described in §13.4.13,
§13.4.14, §13.4.20, and §13.4.22.
Lo! keen-eyed, towering Science! . . .
Yet again, lo! the Soul—above all science . . .
For it, the partial to the permanent flowing,
For it, the Real to the Ideal tends.
For it, the mystic evolution . . .
—Walt Whitman, Song of the Universal (1874)