What's the Deal, Mon?

As I continue to look at the various isms pertaining to belief/nonbelief in deities, I come upon monism. Here is what a few sources have to say about this philosophical position.

There are many monisms. What they have in common is that they attribute oneness. Where they differ is in what they target and how they count.

This entry focuses on two of the more historically important monisms: existence monism and priority monism. Existence monism targets concrete objects and counts by tokens. This is the doctrine that exactly one concrete object exists. Priority monism also targets concrete objects, but counts by basic tokens. This is the doctrine that exactly one concrete object is basic, which will turn out to be the classical doctrine that the whole is prior to its parts.

Neither existence nor priority monism is accorded much respect in contemporary metaphysics, nor are they always properly distinguished. Indeed, the entire monistic tradition is often dismissed as being somewhere between obscure and ridiculous. But there are serious arguments for monism. In particular, priority monism may be especially worthy of serious reconsideration.
~ Stanford Encyclopedia of Philosophy ~

Monism is any philosophical view which holds that there is unity in a given field of inquiry, where this is not to be expected. Thus, some philosophers may hold that the Universe is really just one thing, despite its many appearances and diversities; or theology may support the view that there is one God, with many manifestations in different religions.
~ Wikipedia ~

Monism (Greek monos,"single"), in philosophy, is a doctrine that ultimate reality is entirely of one substance. Monism is thus opposed to both dualism and pluralism. Three basic types of monism are recognized: materialistic monism, idealistic monism, and the mind-stuff theory. According to the first doctrine, everything in the universe, including mental phenomena, is reduced to the one category of matter. In the second doctrine, matter is regarded as a form of manifestation of mind; and in the third doctrine, matter and mind are considered merely aspects of each other. Although monistic philosophies date from ancient Greece, the term monism is comparatively recent. It was first used by the 18th-century German philosopher Christian von Wolff to designate types of philosophical thought in which the attempt was made to eliminate the dichotomy of body and mind.

Although he was not known by the term, the 17th-century Dutch philosopher Baruch Spinoza was one of the most influential monists. He taught that both material and spiritual phenomena are attributes of one underlying substance. His doctrine strongly anticipated the mind-stuff theory.
~ BELIEVE Religious Information Source ~

"Dialectical monism" is a synthesis of Eastern and Western metaphysical concepts. Like other ontological systems, it attempts to describe the world at a fundamental level. It is based on the idea that duality and unity are identical - unity always appears as duality, and duality is always reducible to unity.
~ Dialectical Monism ~

I have mixed feelings about this ism. On one hand, I sort of agree with the main thesis that existence may be one substance, but, then again, I might not. :)

What about you?