DEDUCTION
The Deductive method, frequently called the Platonic method, of philosophical reasoning is a priori, i. e., from known or assumed causes to effects; from fundamental principles to the logical or natural results; from universals to particulars.
This is the method of the Ancient Wisdom or Esoteric Philosophy and of all religions. All religions and esoteric philosophies begin from one fundamental principle which is perceived intuitively, assumed as a logical necessity, or accepted on authority, and all the rest of the philosophy or religion or system of thought is built upon, or hangs pendent therefrom. As we know, the Theosophical philosophy begins with one fundamental Reality, by whatsoever name it may be called, and all the rest is pendent therefrom.
The Platonic or deductive method is that of the Seers and Sages, of the intuitive and spiritually minded, of all ages and religions. It relies on the intuitive perception of fundamental principles and from them deduces the details of its philosophy. The details of the philosophy differ with the degree of the enlightenment and the intellectual capacity of the Philosopher or Teacher and the character and intelligence of the recipients thereof.
The fundamental principles perceived by spiritual intuition remain the same throughout the ages. The names, forms of thought, or theories, vary in value as they reveal or conceal the truth and conform to, or depart from, the facts and laws of nature.
INDUCTION
The Inductive, or Aristotelian, method of philosophical reasoning is a posteriori, i. e., "from effects to causes, from a part to a whole, from particulars to generals, from the individual to the universal."
This is the method of modern scientists who base whatever conclusions they arrive at upon the evidence of discoveries or phenomena before them, quite oblivious of the transitory nature of the evidence and the incompleteness of the discoveries. No satisfactory and enduring philosophy can be founded on the progressively changing discoveries of modern science. Any philosophical system, any comprehensive explanation of the causes of and reasons for things as they are, based on "the solid rock of scientific realities" is liable to be reduced to a mere shifting sand dune or scrap of paper almost any day by some new and startling discovery.
Inductive philosophies are inherently unstable and transitory. H. P. Blavatsky has humorously called the modern inductive philosophers, "philosophicules."
Aristotle's method of accumulating vast numbers of facts laid the foundation for modern science and the scientific method of reasoning from accumulated facts to causes — that is, the Inductive method. Paradoxically, Aristotle's own philosophy is deductive. The explanation of this is that his philosophical ideas were largely drawn from his teacher, Plato.
"Induction can ordinarily give no more than a probable conclusion, because we can never be sure that we have collated all instances." — Funk and Wagnalls" Practical Dictionary
IDEALISM
Idealism is "any theory or philosophy which affirms the universe to be an embodiment of mind or denies the possibility of knowing aught save psychical reality." In philosophical literature the word spiritualism is sometimes used in connection with idealism for the specific purpose of denoting conceptions that are essentially spiritual. Later writers, in the same connection, use the term "philosophical spiritualism" to distinguish what they mean from the modern cult of that name. "Modern Spiritualism," properly so called, began in the United States in 1848 with the "Rochester rap-pings," and is characterized by the belief that the spirits of the dead can communicate with the living in various ways, especially through mediums.
MATERIALISM
Materialism, philosophically speaking, is any theory that assumes to find in matter alone, or in the forces or qualities of matter, a sufficient explanation for the origin of life or the problems of existence. Any theory which denies or excludes the existence of god, soul, mind or spirit, except as products or phenomena of matter — opposed to Idealism.
OBJECTIVE IDEALISM
Theosophy, considered as a philosophy, is an Objective Idealism, because it postulates the Cosmos as the product of Cosmic Ideation and the imbodiment of consciousness. But not a pure Idealism, because it recognises the objective or phenomenal worlds as having a relative reality; being real and objective to all beings who themselves are a part of the objectivity.
The philosophers themselves and the universe about which they philosophize are all alike transitory and phenomenal and therefore unreal. But to themselves it is all very real. In the Theosophical philosophy all things and beings are the product of a Divine Reality which is both immanent and transcendent.
As an Objective Idealism, Theosophy is founded upon one limitless unqualified Reality of which boundless Space and eternal Duration, considered as one, are the best symbols. This idea is adumbrated in Einstein's Time-Space-Continuum when used philosophically — a word or phrase which has another and very technical scientific use, however. This fundamental Principle, or One Reality, is beyond the range and reach of thought, but is perceivable by the highest intuition as the One Reality. The whole objective universe is an emanational unfolding, an ever becoming, as H. P. Blavatsky says, yet its very objectivity, illusive and transitory as it is, is pervaded and sustained by the ever present Reality.
All the manifested universe is compact of hierarchical hosts of Monads, each and all being rooted in the Real and yet having objective existence and relations as long as the manifestation lasts. The Universe itself and all therein is an embodiment of consciousness centers, units of consciousness, or monads. All worlds, subjective and objective, inner and outer, spiritual and material, are compact of monads in varying states of evolution, of ever-Becoming, hence their state at any time is an illusory and transitory one.
Theosophy postulates both Cosmic Ideation and Cosmic Substance on or in which Cosmic Ideation works to produce an objective universe, cosmic substance being the basis of all objectivity. (In this philosophical sense all worlds, including the highest spiritual worlds, are worlds of objectivity or manifestation).
Within the realm of a manifested universe on which philosophical speculation is possible both cosmic Ideation and cosmic Substance are indispensable. One cannot exist without the other. Without Cosmic Ideation Cosmic Substance would remain a formless, lifeless, empty abstraction. Without cosmic Substance no objectivity, no manifestation, not even that of the gods, would be possible. There would be no delimitating factor by which gods, in the plural, could exist.
The Theosophical concept of objective idealism is similar to the Vedantic doctrine of Maya.
Man has within himself the Monadic stream which is rooted in the Real. It is important to understand this and that Reality is ever present here and now. In proportion as this is realized one acquires an inner strength and calm that nothing can disturb. The higher one raises his consciousness the more relativity, differentiation and illusion disappear. As the consciousness ascends towards its source it expands, increases in understanding, discrimination, wisdom, power and love.
In short, within the all encompassing and all comprehending philosophy of Theosophy induction and deduction, idealism and materialism, all have their proper place and value.