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Etymologically theism is indistinguishable from deism except that the former term is derived from the Greek word for God, θεός, while the latter comes from the Latin, deus. The term "theism" was first used by Ralph Cudworth in his Intellectual System of the Universe, in 1678. The terms "theism" and "deism" were employed indiscriminately until the 19th century, when it became customary to restrict deism to philosophical positions involving a denial of some part of the traditional Christian teaching concerning God's providence. Every form of deism includes at least the repudiation of divine revelation. It is on this point that deism and theism are distinguishable. While theism, like deism, is philosophically independent of revelation, the theist does not deny the possibility of divine revelation. While deism tends to regard God as totally outside the material universe, theism favors the notion of an immanent God. In general, theism is monotheistic; since its knowledge is attained by reason rather than revelation, however, theism is not trinitarian, nor does it include such essentially Christian doctrines as the incarnation or the redemption.

According to a popular but not precise use of the term, Christians such as SS. Augustine, Anselm, and Thomas Aquinas are referred to as theists, a form of reference that is justified inasmuch as these men, as well as other Christian theologians, have provided philosophical arguments for the existence and nature of God. Many of these arguments have been adopted by those who are theists in the stricter sense; that is, by men who, without taking a position against the possibility of revelation, limit themselves to knowledge attainable by experience and reason alone.

In contradistinction to pantheism, theism does not regard God and the universe as identical. While God is thought to be immanent to a greater or lesser degree, depending upon the particular system of theism, He is also considered to be transcendent. That is, while God is operative "in" the universe, He is also to some extent beyond it. Finally, the God of theism is a personal Godomniscient, omnipotent, free, and infinitely perfect, a being worthy of unlimited worship. Certain modern philosophies that propose a god-in-process-of-becoming are, therefore, not theistic (see immanence; transcendence).

Early Forms of Theism. It is perhaps impossible to identify with exactitude the first theist in the history of Western philosophy. While there are intimations of theism in the philosophies of anaxagoras and pythago ras, it is generally maintained that plato, in Book 10 of his Laws, provides definite beginnings of a "natural theology" that concludes to the existence of a supreme, intelligent, beneficent spirit (ψυχή). This spirit is the source and governor of all motion in the universe, and even, in some sense, the cause of the being and nature of things in the universe. This divine being, however, supreme among the various "spirits" in Plato's universe, might be inferior to the Ideas (εδη), which completely transcend the universe governed by God.

Plato's argument as found in the Laws was adopted, with significant changes, by Aristotle. Since Aristotle rejects Plato's transcendent Ideas, the first source of all motion, the "prime mover," is for him absolutely supreme, and there is no question of dependence on the Ideas. In Aristotle's Eudoxian universe of concentric spheres, the outermost sphere, while communicating various movements to the inner spheres and ultimately to the earth, itself moves eternally and at an unchanging rate. Therefore, the unmoved mover of this outer sphere must be eternal and immutable; this immutability further entails that the prime mover eternally think one unchanging thought. Since only thought of himself is worthy of such a thinker, the prime mover is "self-thinking thought" or "thinking about thinking" (Meta. 1074b 1535).

Here already is embodied much of what was to become theistic doctrine through the centuries. According to a widely accepted interpretation of Aristotle, however, he himself ought to be classified as a deist rather than a theist, for the Aristotelian prime mover is totally without cognizance of, or interest in, the happenings of the universe; he is completely transcendent. Whether or not this is an accurate interpretation of Aristotle, we can see here two problems that are most perplexing for the theist: (1) How can an unchanging God know a changing universe?(2) How can God be "interested" in the universe and yet be totally unaffected by it, as He must be if He is to be infinitely perfect, orto use the Aristotelian terminology"pure act"? These are questions, of course, for the Christian theologian as well as for the theist, and it was the genius of men such as St. thomas aquinas to suggest reasonable answers to them.

Neoplatonic Emanationism. With the advent of the Neoplatonists new theistic arguments were suggested and new problems raised. While opinion differs on whether the "One" of plotinus is identically God, the fact that the One is absolutely supreme and the source of all the multiple beings of the universe by way of emanation would seem to justify this identification. The One, however, is so utterly transcendent that it cannot be called "thought"; it cannot even be called "being." It is above all thought, above all being. Nothing, in fact, can be predicated of the One. Moreover, nothing can be compared with the One; its eminence is absolute, not a matter of degree. This, too, poses a problem for both theist and theologian: how can one talk about God, or even name Him, without implying that He can be compared with creatures? The use of terms such as "super-good" and "super-intelligent" by pseudo-dionysius, as well as St. Thomas's theory of analogical predication, suggests means of meeting this difficulty.

Plotinus also questioned the way in which God is the cause of the universe. Assuming that the universe emanates from the One, is this emanation necessary, or a result of free choice? For Plotinus, it seems, no freedom is involved; since the One is above thought, no choice is possible (see emanationism). Later philosophers and theologians maintained that an absolutely perfect being ought to be free; yet they had difficulty explaining absolute freedom without ending in some form of divine arbitrariness. The history of theism includes those who, like Plotinus, have seen God as necessitated by His own nature and those who, like william of ockham and R. descartes, have made the Will of God supreme in such a way as to posit a divine capriciousness extending even to the fundamental laws of logic and morality. A third solution, putting into question the absolute supremacy of God, is that of G. W. von leibniz, who maintained that God, whose absolute goodness requires that He create the best possible world, is still determined by "essences" or "possibles" that are somehow independent of Him.

Evil and God's Existence. Another thorny problem facing the theist is that of evil in the universe. Granting an omnipotent, infinitely beneficent God, evil would seem to be impossible. Either God "cannot" prevent evil, the argument runs, and then He is not omnipotent; or He "will not" prevent evil, and then He is not infinitely beneficent. St. augustine proposed one way out of this dilemma, namely, that evil in the universe serves to highlight the good, by way of contrast. Thus no evil is totally evil; it serves a purpose and is, on this account, reconcilable with an infinitely beneficent God. Leibniz, whose theodicy was particularly concerned with the problem of evil, maintained that God creates as much good as is possible, but that all essences or possibles are not mutually compatible, or "compossible." Therefore, if God chooses to actuate certain essences, other essences become incapable of actuation. Evil, then, has its source, not in God, but in essences. For St. Thomas and scholastics generally, evil is an absence of good, a "nothing," and as such requires no cause.

These proposals, of course, are particularly intelligible when understood in relation to the doctrines of origi nal sin and Redemption. The theist, having no access to such mysteries, is left with a problem that is practically insoluble. Nor does this seem strange when one considers that even his most elementary problem, the problem of whether God exists, has been the source of so many difficulties. Indeed, a man as brilliant as Immanuel Kant was to reject as inconclusive all traditional proofs and to substitute one of his own, based on what he took to be the natural foundation of ethical conduct, the categorical imperative. Yet the Kantian argumentfor which Kant himself never claimed scientific certitudehas few adherents today.

Another approach to a natural theology, this one based on modern science, is outlined by P. teilhard de chardin in his Phenomenon of Man. Here God is considered as an end toward which the universe is tending in its evolutionary process. While Teilhard's thesis is appealing in its timeliness, its emphasis on the dynamic, and its possibilities for a better understanding of the relation of the universe to God, it does not employ a logic sufficiently rigorous to compel assent.

In brief, the development of theism, from Plato to the present, can be regarded as a confirmation of St. Thomas's observation that it is extremely difficult for man, by reason alone, to arrive at a knowledge of God that is evidently true and not compounded with error (Summa theologiae 1a, 1.1).

See Also: god, proofs for the existence of; rationalism.

Bibliography: d. j. hawkins, The Essentials of Theism (New York 1949). j. j. mclarney, The Theism of Edgar Sheffield Brightman (Washington 1936). p. a. bertocci, The Empirical Argument for God in Late British Thought (Cambridge, Mass. 1938). g. santinello, Enciclopedia filosofica, 4 v. (Venice-Rome 1957) 4:11078. r. eisler, Wörterbuch der philosophischen Begriffe, 3v. (4th ed. Berlin 192730) 3:231. a. e. taylor, Encyclopedia of Religion and Ethics, ed. j. hastings, 13 v. (Edinburgh 190827) 12:261287. f. solmsen, Plato's Theology (Cornell Studies in Classical Philology 27; Ithaca 1942). b. p. bowne, Studies in Theism (New York 1879). s. harris, The Philosophical Basis of Theism (New York 1883). f. w. newman, Theism, Doctrinal and Practical (London 1858).

[r. z. lauer]

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