So far true metaphysics is a monism of substance, in the sense that all things are substances and that all substances, however different, are members of one substance, the whole universe of body and spirit.
To Xenophanes, the founder of Eleaticism - whom he must have known, even if he was never in any strict sense of the word his disciple - Parmenides was, perhaps, more deeply indebted, as the theological speculations of that thinker unquestionably suggested to him the theory of Being and Not-Being, of the One and the Many, by which he sought to reconcile Ionian " monism," or rather " henism," with Italiote dualism.
We see it in Huxley, and still more in Haeckel, whose materialism (which he chooses to term "monism") is evidently conditioned by ignorance of the history and present position of speculation.
His philosophy is an attempt to reconcile monism (Hegel) and individualism (Herbart) by means of theism (Leibnitz).
Materialism supposes that this mechanical order is the real world and the only real world - mechanical monism.'
Anyhow, whatever the method or interpretation is to be, idealism, even more fully than materialism, is pledged to monism and to the rejection of dualism.
But in other parts of his works he suggests that mind and matter are two different aspects of that which is the basis of all things - a monism which is not necessarily materialistic, and which, in the absence of further explanation, constitutes a confession of failure.
To this extent monism is justified; but it becomes mischievous if it prompts us to ignore important differences in facts as they present themselves to our intelligence.
All forms of monism from Plotinus downwards tend to ignore personal individuality and volition, and merge all finite existence in the featureless unity of the Absolute; this, indeed, is what inspires the passion of the protest against monism.
Hegel's is an intellectualist monism, explaining matter, sensation, personal individuality and will as forms of thought.
The doctrine of Schopenhauer and von Hartmann is a monism of cosmic will which submerges the individual no less completely than Hegelianism, though in a different manner.
Haeckel's monism is mere materialism dignified by a higher title.
It is generally admitted that he had no accurate knowledge either of Spinoza, whose monism he advocated, or of Kant, whose critical philosophy he so fiercely attacked.
But with these advances came the danger of falling into error from which common-sense dualism and naturalistic monism were free.
They also exhibit a variation from the characteristic dualism of Gnosticism into monism, in their conception of the fall of Sophia and their derivation of matter from the passions of the fallen Sophia.
Moreover, there is no real opposition between monism and dualism, for there can very well be one kind of being, without being all body or all soul; and as a matter of fact, Aristotelian realism is both a monism of substance and a dualism of body and soul.
It is in any case unfair to decide questions by disparaging terms, and to argue as if the whole choice were between materialistic or idealistic monism, leaving realism out of court.
But this very dualism is also monism: both bodies and souls are substances, as Aristotle said; and we can go farther than Aristotle.
In this case metaphysics generally will have to recognize three monisms, a materialistic monism of body, an idealistic monism of soul, and a realistic monism of substance, which is also a dualism of substances.
But a term so equivocal, leading to an antithesis so misleading as that between monism and dualism, can never represent the real difference between metaphysical schools.
Certain scientific odium attaches, and substitute ` monism ' for it " (Last Words on Materialism, 273).
But if a philosophy makes force an attribute of matter only, as his does, it will recognize nothing but matter possessing force, and will therefore be materialism as well as monism, and in short materialistic monism.
Like all true followers of Kant, Riehl prefers epistemology to metaphysics; yet in reality he founds a metaphysics on epistemology, which he calls " critical realism," so far as it asserts a knowledge of things beyond phenomena, and " critical monism," so far as it holds that these things are unlike both physical and psychical phenomena, but are nevertheless the common basis of both.
Metaphysical dualism postulates the eternal coexistence of mind and matter, as opposed to monism both idealistic and materialistic. Two forms of this dualism are held.
Hence the theory is a kind of monism, inasmuch as it confessedly does not assert the existence of matter save as an intellectual postulate for the thinking mind.
It is a self-destructive dualism, a confessedly one-sided monism, agnostic as to the fundamental problem.
The severing of the natural and the supernatural, the Catholic monism, the unity of the life of faith as willed by God.
By his recognition of an apparent plurality supplementary to the real unity, he effected the transition from the " monism " or " henism " of the first physical succession to the " pluralism " of the second.
The Stoic system is in brief: (a) materialism, (b) dynamic materialism, lastly (c) monism or pantheism.
But until dualism had been thought out, as in the Peripatetic school, it was impossible that monism (or at any rate materialistic monism) should be definitely and consciously maintained.
Its most valuable lessons to the world were preserved in Christianity; but the grand simplicity of its monism slumbered for fifteen centuries before it was revived by Spinoza.
It accounts, too, for his polemic on the one hand against a Substantial Soul, a Buddhistic Absolute, an Infinite Spiritual Substance; on the other hand against the no less mysterious material or dynamic substratum by which naturalistic Monism explains the world.
Nichiren taught a philosophical monism in the 13th century which is the basis of a vigorous sect at the present day; and the " True Sect of the Pure Land," founded by his older contemporary Shin-ran, and now the most numerous, wealthy and powerful of the Buddhist denominations, has dropped the original Gotama altogether out of sight, and permits worship to Amida alone, the sublime figure of " Boundless Light," whose saving power is appropriated by faith.
MONISM (from Gr.