book review

What can science learn from Paul Tillich?

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What can science learn from Paul Tillich?

Systematic Theology
by Paul Tillich
Chicago University Press, 1963, 3 volumes, 921 pages
Reviewed by T.J. Nelson

P aul Tillich was one of the greatest theologians of the 20th century. Some Christians regard the ideas, which are laid out in this monumental three-volume, five-part work, as heretical, even atheistic. Others regard it as an abstract and unapproachable theory. But Tillich followed the tradition of theologian-turned-philosopher. His theology was shaped by his experience in World War I; writing in the 1950s, he was also strongly influenced by the existentialists. Especially in Part II, “Being and God” and Part III “Existence and the Christ” he develops a unique ontology that is underappreciated by philosophers and mostly unknown to scientists. This is unfortunate, because he has many interesting ideas.

Mentioning God sometimes makes scientists uncomfortable. We perceive religion as a collection of interesting stories about an entity whose existence has not yet been empirically demonstrated, and we're reminded of hours sitting uncomfortably as children in Sunday school being sermonized to. But Tillich is that rare thinker who bridges religion and secularism. There are, regardless of one's religious beliefs, some very profound concepts here. Of all theologians, it is Tillich who takes science the most seriously.

1. Unification of essential and existential being

Much of this dense and complicated work concerns itself with issues of interest mainly to religious people: the value of asceticism, the problems with polytheism, and of course Christ. Tillich's view of God is abstract and impersonal. Some religious thinkers accuse him of pantheism, a charge he denies repeatedly in this book. But Tillich is also unequivocal in his rejection of Biblical literalism. Those who reject religion because of an absence of proof that God exists, he wrote in Theology of Culture, have not only not refuted religion, but have done it a considerable service. Fundamentalist interpretations of religious texts, particularly cosmology, he wrote, are harmful.

Tillich's ontology is based on the duality between essential and existential being. Essential being is what characterizes ‘finitude’ (Vol. 1, p.202). It is our potential, which gives us the power of being. Existence means the actual world as it really is. Tillich regarded this much as we view the unification of electromagnetism and the weak force:

“As being-itself God is beyond the contrast of essential and existential being .... Logically, being-itself is ‘before,’‘prior to,’ the split which characterizes finite being.” (Vol.1, p.236)

He goes on to say:

“ [T]he question of the existence of God can neither be asked nor answered ... the answer—whether negative or affirmative—implicitly denies the nature of God. It is as atheistic to affirm the existence of God as it is to deny it.” (Vol.1, p.237)

What does this mean? It means that God is the ontological structure of being, but is not subject to this structure himself (p.239). Taking his cue from Parmenides, he says “if one asks why there is not nothing, one attributes being even to nothing.” God transcends the distinction between being and non-being; he is ‘being-itself.’ “God cannot be called a self, because the concept ‘self’ implies separation from and contrast to everything which is not self.” (p.244) Since God is the ground of being, he writes, he is not subject to the two categories of relation, which are causality and substance.

2. Aseity

Tillich contrasts three concepts of God. The first is that of the fundamentalists, who view God as a being who has existence and brought the world into existence. Against this view, says Tillich, the arguments of naturalism are valid. He writes: “Theology must accept the antisupranatural criticism of naturalism.” (Vol. 2, p.6)

The second concept is the abstract, deistic god of Spinoza and Johannes Scotus Eriugena (famous for getting stabbed to death by his students with their pens), who said God is the creative ground of all natural objects. That is, God is a creator but not created, while man is both a creator and created. The world ultimately returns to the state of neither creator nor created. According to this concept, man is God's way of understanding himself. Tillich dislikes this one as well, saying this God is too close to being synonymous with ‘universe’ and is therefore pantheistic and superfluous.

Tillich's third concept forms the basis for his theology. For Tillich, God = being-itself = love (Vol.1, p. 279); he is also beyond the distinction between potentiality and actuality. God does not want anything. He is not above things, but “nearer to them than they are to themselves.” “Where divine love ends, being ends.” Tillich does not say what divine love is, even though it is a widespread concept in Christianity. (I have not seen anyone else define it adequately, either; my impression is that it might be an emotional feeling of unification that is passed on to the believer during a religious experience. This still seems a bit vague.)

He rejects the concept of omnipotence: “It makes God into a being alongside others, a being who asks himself which of innumerable possibilities he shall actualize. It subjects God to the split between potentiality and actuality—a split which is actually the heritage of finitude. It leads to absurd questions about God's power in terms of logically contradictory possibilities.” (Vol.1, p 273) Tillich says heaven, earth and underworld are not real places, just symbols. Omnipotence, omnipresence, and omniscience are symbols that must be reevaluated. God is in everything at every moment; God is what resists nonbeing. (Vol. 1, p.187)

The idea of God as being-itself comes from the theological concept of aseity, which means that God does not require anything else besides himself in order to exist. This, said Tillich, is not good enough. If God ‘exists,’ then he must be dependent on something else for his continued existence; otherwise it is possible to imagine that he did not exist. This is unacceptable, says Tillich, because it would make him less than omnipotent.

Western religions also hold that creation is reversible: the instant God stops exerting effort, the universe would immediately collapse into nonexistence. This is called divine conservation. Divine conservation means that matter, energy, space and time are only byproducts of some other process, like light given off when something is heated. In other words, they are proposing a new state of matter and energy more fundamental than anything we can perceive. (However, no field equations yet.)

3. Individual vs. collective soul

Tillich says the concept of a soul has “lost its usefulness for a strict theological understanding of man, his spirit, and its relation to the divine Spirit.” (Vol.3, p.24) He questions the doctrine of humans having an immortal soul. Immortality, he writes, is used in a non-Christian, pseudo-Platonic way meaning continuation of the temporal life of an individual after death without a body. This idea, he says, must be rejected because it introduces a dualism between soul and body. (Vol.3, p.409-410).

He writes: “Sin is the sting of death, not its physical cause. It transforms the anxious awareness of one's having to die into the painful realization of a lost eternity.” (Vol.2, p.67-68)

Science can use these concepts in a different way. These days, we emphasize the individual, and we assume the soul is a part of an individual person; but in ancient times the most important entity was not the individual, but the tribe. Unlike an individual, a tribe could have immortal life, and it could die out forever. Few would doubt that a tribe has a spirit and a soul, and that this soul could be contaminated and injured when the tribe commits some evil or ‘sinful’ act, sin being defined as something that leads to the death of the tribe. Perhaps this is what was actually meant.

This view seems to be gaining currency, at least among some Jewish thinkers. Maybe we've been misinterpreting all this religion stuff for hundreds of years, while a viable science of sociology lay just under our noses, sitting unread in the top drawer of every hotel nightstand.


Systematic Theology is a profound, 900-page work of dense religious philosophy, somewhat abstract in places; some readers may wish to start with Theology of Culture first. In a sense, it could be construed as an astonishingly clever proof of God's existence: in effect, he redefines existence to mean God. Even if you're not convinced, Tillich's ideas are potentially of tremendous value to science. This is a type of religion even atheists can appreciate. If my Sunday school teachers had talked like this, I might have actually listened instead of sneaking outside to observe the behavior of the ants crawling across the sidewalk. And for sure I would have learned a lot more about Christianity.

On the other hand, if they had done that, my Sunday school would never have found out about their ant problem.

Reviewed on this page

Systematic Theology
by Paul Tillich

See also

The Soul of the World
by Roger Scruton

Parmenides and the Way of Truth
by Richard G. Geldard

Being and Time
by Martin Heidegger

The Oxford Handbook of Philosophy of Religion
by William J. Wainwright, ed.

It's Not the End of the World It's Just the End of You
by David P. Goldman

On the Internet, no one can tell whether you're a dolphin or a porpoise

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jun 28, 2015