i found this in wikipedia

The basic premise of Mage: The Ascension is that everyone has the capacity, at some level,

to shape reality. This capacity, personified as a mysterious alter-ego called the Avatar, is

dormant in most people, who are known as sleepers, whereas Mages (and/or their Avatars) are

said to be Awakened. Because they're awakened, Mages can consciously effect changes to

reality via willpower, beliefs, and specific magical techniques.

The beliefs and techniques of Mages vary enormously, and the ability to alter reality can

only exist in the context of a coherent system of belief and technique, called a paradigm. A

paradigm organizes a Mage's understanding of reality, how the universe works, and what

things mean. It also provides the Mage with an understanding of how to change reality,

through specific magical techniques. For example, an alchemical paradigm might describe the

act of wood burning as the wood "releasing its essence of elemental Fire," while modern

science would describe fire as "combustion resulting from a complex chemical reaction."

Paradigms tend to be idiosyncratic to the individual Mage, but the vast majority belong to

broad categories of paradigm, e.g., Shamanism, Medieval Sorcery, religious miracle working,

and superscience.

In the Mage setting, everyday reality is governed by commonsense rules derived from the

collective beliefs of sleepers. This is called the consensus. Most Mages' paradigms differ

substantially from the consensus. When a mage performs an act of magic that does not

seriously violate this commonsense version of reality, in game terms this is called

coincidental magic. Magic that deviates wildly from consensus is called vulgar magic. When

it is performed ineptly, or is vulgar, and especially if it is vulgar and witnessed by

sleepers, magic can cause Paradox, a phenomenon in which reality tries to resolve

contradictions between the consensus and the Mage's efforts. Paradox is difficult to predict

and almost always bad for the mage. The most common consequences of paradox include physical

damage directly to the Mage's body, and paradox flaws, magic-like effects which can for

example turn the mage's hair green, make him mute, make him incapable of leaving a certain

location, and so on. In more extreme cases paradox can cause Quiet (forms of madness that

afflicts mages and may leak into reality), Paradox Spirits (nebulous, often powerful beings

which purposively set about resolving the contradiction, usually by directly punishing the

mage), or even the removal of the Mage to a paradox realm, a pocket dimension from which it

may be difficult to escape.

In Mage, there is an underlying framework to reality called the Tapestry. The Tapestry is

naturally divided into various sections, including the physical realm and various levels of

the spirit world, or Umbra. At the most basic level, the Tapestry is composed of something

called Quintessence, the essence of magic and what is real, in game terms. Quintessence can

have distinctive characteristics, called resonance, which are broken down into three

categories: dynamic, static, and entropic.