Modern Theosophy holds that existence embraces more than the material realm. Moreover, a lack of knowledge about these higher aspects of reality leads many people to feel confused, conflicted, and unsure of their purpose in life.
Most Theosophists believe that we can gain knowledge of the Real, both in the universe and in human beings, by means of a holistic spiritual practice that includes study, meditation, and service.
Here are some of the basic ideas offered in Theosophical literature:
Behind everything seen or unseen there is an eternal, boundless, and immutable absolute Reality, which is beyond the range of human thought. Both matter and consciousness (or spirit) are the two polar aspects of this Reality.
The universe is cyclical in nature
In fact there have been many universes. Each one manifests, develops, and dissolves back into the absolute Reality. After a period of cosmic rest, a new universe appears again.
Unity of all Life
Because everything proceeds from this one Reality, there is only one common life that pervades and sustains the whole universe. Every form of life is an expression of this unity.
Invisible dimensions or planes
The visible universe is only its densest part of this Reality. Invisible dimensions or planes of extremely subtle kinds of matter-energy interpenetrate the physical world. Knowing this helps us to understand many things in the universe that are otherwise baffling.
The universe has a purpose
The entire system, visible and invisible, is the scene of a great scheme of evolution, in which life moves to ever more expressive forms, more responsive awareness, and more unified consciousness
There are no mechanical laws. The universe is pervaded by an immense intelligence, which is both present in the world and beyond it. Therefore intelligence is at the basis of all laws of nature. What most people consider “supernatural” is a manifestation of these otherwise unknown laws.
We are all One
Human consciousness is in essence identical with the ultimate Reality. This Reality is the root of our real Self, and it is shared by all beings. Thus at the core we are united with one another.
The gradual unfolding of this Reality within us takes place over a long period of time through reincarnation, which is one aspect of the cyclic law that is seen everywhere in nature.
The cycle of reincarnation is ruled by the law of karma, or cause and effect. The doctrine of karma holds that each cause produces an effect like itself, and that this effect will eventually return to the one who has acted. As St. Paul says, whatever we sow, we will reap. The law of karma enables us to weave our own destiny through the ages. It is the force that ensures justice in the universe, because it means that everything we experience is the fruit of our actions in the past—in this life or another. This offers great hope, because it gives us the opportunity to create our future by what we do in the present.
The human pilgrimage takes us from the Source, where we begin as an unconscious part of the One Divine Reality, and leads us through the experience of the many, to finally take us back into union with the One, but now in full awareness. Our goal is thus to consciously realize ourselves as integral parts of the One, no longer polarized between consciousness and matter, or self and other. This realization is known as enlightenment.
Content extracted from the Theosophical Society in America web page.