Difference between GBM and MBM

Before definition of MBM (Medial Black Magic) all MBM was called GBM (Greater Black Magic), so it can bring some confusion between the two.

In Black Magic Book of Aquino, Medial Black Magic, is discussed as follows:

" It is easy to focus strongly and exclusively on either one or the other of these two categories, so much so that we miss that grey area wherein they blend. Let us call this Medial Black Magic (MBM).

MBM involved the use of the Magical Link in its simplest, most direct form in an operative context. Unlike LBM, in which the magician uses forces and features which are of the objective universe to accomplish his goal, MBM has similar goals but uses metaphysical means - the Magical Link - to realize them. It is not as "pure" as true GBM.
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The difference between GBM and MBM is a difference in intent. 
MBM plans to change the subjective universe to cause a change in the objective universe. 
GBM intends to change the subjective universe  to perceive oneself (own SU) or cause a change in the subjective universe, although it can cause an unintended change (good or bad depending on the perspective) in the objective universe through synchronism.

The final objectives of MBM and LBM are the same.

Difference between LBM and GBM

"By 1970 this "Satanic tent revivalism" was already history. BM was being refined into LBM and GBM: the former involving operational goals by setting in motion whatever OU forces, known and obscure, necessary to achieve them or at least increase their probability; the latter being a focus and intensification of consciousness, enhanced by "ritual chamber" sensory reinforcement, to perceive oneself and the contents of one's SU with greater intelligence and precision.
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While my MindWar book is written for exoteric audiences, it could from an esoteric perspective be considered a LBM "grimoire"; and it constantly emphasizes the ethical issues of its application. It will give you some idea of just how dark and deep an ocean you're diving into if you really want to venture into this subject."

- Michael Aquino in 600 club


In "Black Magic" Dr. Aquino writes on Lesser Black Magic:

Lesser Black Magic (LBM) is the influencing of beings, processes, or objects in the objective universe by the application of obscure physical or behavioral laws.

LBM is an impelling (encouraging, convincing, increasing of probability) measure, not a compelling (forcing, making inevitable) one. The object if to make something happen without expending the time and energy to make it happen through direct cause-and-effect.

and on Greater Black Magic:

Greater Black Magic (GBM) is the causing of change to occur in the subjective universe in accordance with the will. This change is the subjective universe may cause a similar and proportionate change in the objective universe (MBM).

Later two divisions between the kinds of GBM that exist is made:

You undertake a GBM working because you want to understand something or because you want to change something. The former type may be referred to as an illustrative working, while the latter is often called an operative working. Each takes effect by expanding and/or altering your subjective universe, which then exerts a corresponding and proportionate influence upon the objective universe - and other subjective universes - via the Magical Link phenomenon.