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Oct 11, 2018

Can Philosophy Provide Evidence for God’s Existence? Part 2

Joseph Miller

This is the second article in the series on philosophical evidence for God

In our last post, we discussed the logical necessity for the existence of an uncaused being (existing through itself) which is the cause of everything else that exists. Now, we will demonstrate that the uncaused being must be absolutely unrestricted and utterly simple.

Boundaries/Restrictions are limiting and exclusive

Boundaries/restrictions exclude. If something has the boundaries of a square it cannot have the boundaries of a circle or a triangle in the same respect at the same time and in the same place. For millennia philosophers have recognized that having fewer boundaries or restrictions allows for unification of seemingly disparate realities.

An example from physics is the concept of a field. The properties of electricity differ from those of magnetism but are unified in the relatively less-restricted electromagnetic field. Space and time are very different realities that become unified in a gravitational or space-time field. The implication here is that fields, which have less boundaries/restrictions and are thus more inclusive, can unify lower orders of being without being subjugated to the boundaries of the things that they unify.

Less boundaries/restrictions and more inclusion equal greater simplicity

Here we want to put forth the principle of simplicity as espoused by the Greek philosophers like Thales, who proposed water as the absolutely simple element from which all other matter is composed. For Thales, Parmenides, Plato, and Aristotle, the simpler a reality is, the fewer intrinsic and/or extrinsic boundaries it has. As we have just seen, boundaries exclude. Hence, greater simplicity means less intrinsic and extrinsic boundaries which entails less exclusion within itself and with other beings, which further entails greater possibility for interaction and interrelationship with other realities.

What would absolute simplicity be like?

Thus far, we have discovered an important metaphysical principle: the less exclusive and more compatible a thing is, the fewer restrictions or boundaries it has to limit its mode of being—or, as the aforementioned philosophers would put it, the simpler it is. If we take this concept to its logical end, an absolutely simple being would have no boundaries or restrictions. In other words, it would not be restricted to existing in this way or that way; nor be restricted to existing here instead of there; nor be restricted to existing now instead of then; but simply be. Furthermore, it would be able to unify all other being within itself because it would have no restrictions to give rise to exclusion or incompatibility.

The Absolutely Simple Being and the Uncaused Being

Now we’ll explore whether this absolutely simple being and the uncaused being (described in the previous post) might be one and the same.

In other words, now that we have looked at the arguments for an uncaused being and absolute simplicity, we are in a position to ask the question, “Is this uncaused being absolutely simple?”

Absolutely Simplicity Reviewed

Let’s start by reviewing the concept of simplicity. As presented above, any being that is not absolutely simple by definition has boundaries or restrictions. Thus, even the electromagnetic field, with its ability to unify electricity and magnetism is still distinct from, and incompatible with, other kinds of fields, for example the gravitational field. So, the question of whether an uncaused being is absolutely simple is really a question of whether or not an uncaused being can have restrictions.

Existence and Essence – Two Key Principles

Recall that an uncaused being exists through itself. The proof that an uncaused being must be absolutely simple is centered on the following fundamental Thomistic principles:

  1. Existence – The act of being
  2. Essence – A particular way of existing (e.g., existing as a horse, or a rock, or a proton)

According to Aquinas, all created (i.e. caused) beings are composed of both essence and existence. Thus, every real created being is a composition of “what it is” and “its act of existing”. It is essence that limits something to a specific type of being (e.g., a horse). It is the act of existing that makes something real as opposed to imagined. Thomas deduced that these limited real beings must have their source in simple or pure existence – that is, existence not restricted or bounded by essence. He referred to this pure being as “being in itself”.

He recognizes pure being as not only unrestricted but uncaused, because it constitutes the ground of all other beings. Thus, if it had a cause, that cause would need to come from outside of all being – a logical contradiction in terms (see post #1). This purely simple being is the cause of all caused beings, and because it has no restrictions or boundaries is able to unify all lower orders of reality.

Could There be More than One Unrestricted Being?

This brings up a frequently asked question, “Why does Thomas believe that there is only one simple and uncaused being? Couldn’t there be two or even more?”

His position is based on the following premises:

  1. If there are multiple uncaused beings, there must be a difference between those beings. If they are identical in all respects then they are one.
  2. If there are differences, then at least one of those beings must be restricted (i.e., limited by essence and thus not absolutely simple). But given that there can be no restrictions in “pure being” there must be only one unrestricted being.

And This We Call God

Thus far we have used philosophical inquiry to discover that there must be one, absolutely-simple, uncaused being that is the cause of all other beings. Now we’ll examine if philosophy can tell us anything more about this uncaused being.

We have already examined how there must be oneabsolutely-simpleuncaused being that is the cause of all other beings; but can we really call this being God?

Thomas Aquinas, after using philosophical terms to describe God, sometimes closes his argument with the expression, “and this we call God”. (See for example Summa Theologiae > First Part > Question 2 > Article 3).

Here we will follow his lead and acknowledge that the one, absolutely-simple, uncaused being that is the cause of all other beings is in fact God. Are there any other attributes of God that can be known through philosophy? The following is a list of divine attributes that philosophers have associated with God.

God is:

  • Personal
  • Supremely Good
  • Omniscient
  • Omnipotent
  • Omnipresent
  • Eternal
  • Immaterial
  • Transcendent and Immanent

Although each of these can be logically derived, their proofs are less rigorous than what we’ve seen. Furthermore, some give rise to seemingly insurmountable problems. Check out these links for information from Fr. Spitzer on philosophical discussions of free will v. God’s omniscience and suffering v. God’s omnipotence.

Because many philosophers see no way to get beyond the stripped-down description of God as merely a creator deity, this depiction of God has come to be known as the God of the philosophers. The challenge for Christian philosophy is to show the seamless complementarity between the philosophers’ God and the personal, loving, God of Christian revelation. For Thomas Aquinas, proof of the divine attributes is rooted in God’s perfection. For whatever a creature possesses in a partial and imperfect way, God, as the source of all being, must possess in a complete and perfect way.

This article was first posted as part of a series on the Magis Center blog. It has been republished here with permission. 


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Joseph Miller is the Executive Director of the Magis Center