There are two main branches of Arcane Knowledge you must know to proceed amongst the Rooms of the Annexe:

The Knowledge of Numbers: Numerology

The Knowledge of Matter: Alchemy

Concerning Numbers:

There cannot be Nothing.

There is therefore Something.

What is the Nature of that Something?

It is whatever it could Fundamentally Be.

Numbers are the Guide to Reality. What may be expressed in Abstractions can therefore Exist.

Concerning Matter:

For there to be Something there is [redacted; see Godel]

There is always Change.

Matter is the Matrix of Change. That is the Key.