Neptune can be understood in part by defining what it is not. Even more than Uranus, it is an energy that negates everything that Saturn stands for. If Saturn is reality, Neptune is unreality. If Saturn is an aspect the ego, Neptune is denial of the ego. If Saturn is our notion of time and space, Neptune is outside time and space, in either a non-dimensioned or an infinitely dimensioned universe. Neptune symbolizes the truth and divinity perceived by mystics. At the highest level, Neptune is Nirvana, where all individuality is merged into an infinite oneness of being and consciousness.
To b able to handle Neptune and Saturn at once is difficult. One must be able to play he game of reality completely and with total conviction, exact as if it were real in the ultimate sense, while at the same time knowing in one's heart that is not. one must be able to live in the universe of Saturn, being responsible and aware of its laws, while at the same time not require it for support. The addiction to structure that we referred to under Saturn is not permissible with Neptune. This is what is called detachment: playing the game for real yet knowing that it is not.
One cannot even be attached to oneself, because the ego, the form one's being that one calls oneself, is also not ultimate real. This is why Neptune is an ego-denying energy. In the presence of Neptune, the illusion of the ego becomes clear. The illusion is not so much the awareness of having an ego, as it is of being an ego. On a low level, Neptune represents experiences that becloud the ego, which, in order to function, needs a sense of a secure ultimate reality. Thus Neptune symbolizes illusion, mystery, confusion, and crises in which one's ego is severely defeated.
Neptune is the next stage beyond Uranus in the encounter with the transcendent aspects of existence. If Saturn represents normal reality and the consciousness that deals with that reality, and Uranus represents those energies that break through normal reality so its structures cannot become too deadening, then Neptune represents the total negation of all the principles of normal reality. Neptune is often described as illusion, while Saturn is said to represent truth. The relations is actually the reverse: Saturn is the illusion that there is a reality that is truth; Neptune is the truth that there isn't. In some respects, Neptune is more truly chaotic than Uranus, in that Neptune can be the formless void before any structure is imposed upon it. Yet on closer examination we could say that Neptune symbolizes the universe in which all truth is simultaneously true, even the contradictions!
In its manifestations in ordinary life, Neptune can represent either illusion or mystical illumination, depending on one's level of spiritual evolution. For this reason, Neptune can represent the highest and lowest aspects of human experience, the most beautiful and painful of human emotions. The task of mastering Neptune's energies is one of the most difficult, and very few do it completely. I suspect this is so because to master the energy that Neptune represent requires being able to accept all its truth at once. To do this means that one cannot perform the acts of exclusion and selection that are require in order to create - that is, to incarnate into - a physical universe under Saturn. If one really masters Neptune, one probably does not incarnate into this world. The mere fact of such incarnation suggest that Neptune has not been mastered and probably will not be in this lifetime, except for the occasional Bodhisattva who incarnates totally realized for the sake of guiding others to the truth. We should not be sorry about this; we should simply go about doing what is to be done and learning what is to be learned.
It is important to learn that all the energy that comes with being alive has its origin in the universe of Neptune, and that if we cut ourselves off from Neptunian energy with walls of Saturn, wee ultimately cut ourselves off from life. Uranus makes the break in what armors us against the ultimately real, while Neptune gives a glimpse of the ultimately real itself.
from Horoscope Symbols ~ Robert Hand