What is the relationship between Ignorance and Knowledge as described by Sai Baba, and what analogies does he use to explain it?

In Chapter 39, Sai Baba presents a unique relationship between Ignorance (Ajnana) and Knowledge (Jnana). He states that Knowledge is not the opposite of Ignorance but is instead veiled by it. As he puts it, 'Knowledge is veiled by Ignorance,' and once this veil is removed, Knowledge shines forth naturally. To clarify this, Baba provides several powerful analogies. He compares Ignorance to a membrane covering a fetus, dust on a mirror, ash covering a fire, and moss concealing pure water. In each case, the underlying reality (Knowledge) is perfect and self-existent; it is merely the obstruction (Ignorance) that must be removed.