As individuals most of us feel that we only exist within our skin and we sense no connection to the outside world. This creates the deception that everything outside our skin is alien and potentially hostile. It is this isolationist attitude that allows us to carelessly destroy the very environment that sustains us and irrationally see all other life forms as possible threats. However, the overwhelming evidence is that the separateness we feel is simply an illusion.
Oneness is the understanding that we are not isolated individuals within Nature. We are fundamentally connected to all the natural processes of this planet and ultimately to the Universe - the creator of all physical things.
The first step in understanding oneness is the realisation that without this planet we would not have the nutrition; water; a protective atmosphere; the correct temperature or the air we need to exist. Therefore the earth is as essential to our existence as our own internal organs. Yet most of us feel no connection to earth's environment. We only identify ourselves with our bodies; although the environment is just as crucial to our survival as our body. Needless to say, the sensation of separateness is essentially due to our ego, which prevents us from seeing things as they truly exist.
We probably feel more connected to our body since we feel we have some level of control over what it does; whereas we have no control over the environment. However, the control we have over our bodies is very superficial. Sure, we can walk, talk and strike a blow, but the fact remains that we have as little control over our biological systems, as we do over the environment. For example, we can't directly regulate our heart; control the secretions of our glands; coordinate our digestion; will our cells to divide; or organise our nervous system.
Just like environmental processes, the processes of the body occur spontaneously without any conscious attention. Logically, if what is outside our body is just as essential as what is inside our body and we have no control of either; we can then conclude that both our body and our environment are one and the same. Nature is controlling both equally, making ourselves and the natural world one self perpetuating unity.
Oneness has also been theorised in particle physics. Physicists explain the unity of all things with the 'unified field'; an "universal ocean" that contains all possible things. The unified field exists at the deepest sub-atomic level possible and connects everything in the Universe. All the forces and material objects; including us, are the result of vibrations on the unified field.
The illusion of remoteness we experience as a species is the cause of all the difficulties the world is currently enduring. If we could simply overcome our egocentricity and become mindful of the unity of all things; we would not be on our current course of escalating wars, hatred and environmental destruction.
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