Arguments for theism

How one met someone can significantly affect the shape of one’s relationship with them for years to come. Therefore, we can imagine that what reasons convinced one to believe in God can significantly affect the shape of one’s relationship with God. If this is right, and if God has a plan for a particular kind of relationship with a person, then God might have reason to keep the person from being convinced by some evidence for the existence of God, in order that the person might instead come to be convinced by reasons that will set the stage for the particular shape of relationship God wants.

In particular, it would not be surprising if some of the more abstract philosophical arguments for the existence of God, while perfectly fine as arguments, might not be fitting for leading a particular individual into a deeply interpersonal relationship. And if so, we could imagine that God could keep the person from being convinced by such arguments, in order that the person might come to belief in a different way.

But it all could depend on the person. We are broken in different ways, and God has different plans for us all.

Samuel Clarke on our ignorance of the essence of God

At times I am made uncomfortable by this objection to arguments for the existence of God: there feels like there is something fishy about inferring the existence of a being about which we know so very little. It may be that theism is the only reasonable explanation of the universe’s existence, but if we know so very little about that explanation, can the inference to the truth of that explanation be a genuine version of inference to best explanation?

Newton's disciple Samuel Clarke has a nice answer to this objection:

There is not so mean and contemptible a plant or animal, that does not confound the most enlarged understanding upon earth; nay, even the simplest and plainest of all inanimate beings have their essence or substance hidden from us in the deepest and most impenetrable obscurity.

In other words, all our ordinary day-to-day inferences are to things whose essence is hidden.

It may be thought that now that we know about DNA, we do know the essences of plants and animals. But even if that is true, which I am sceptical of, it doesn’t matter: for belief in plants and animals was quite reasonable even before our superior science. And even this day, our knowledge of the essences of the fundamental entities of physics (e.g., particles, fields, wavefunctions) is basically nil. All we know is some facts about the effects of these entities.

Some sound theistic arguments

Argument 1:

1. Possibly, the Principle of Sufficient Reason (PSR) is true.
2. Necessarily, if the PSR is true, then there is a causally efficacious necessary being.
3. Therefore, possibly, there is a necessary causally efficacious being.
4. Therefore, actually, there is a necessary possibly causally efficacious being.

Argument 2:
Let @ be the actual world. Say that a being is omnipotent* provided it is omnipotent at at least some explanatory point in the history of the world (so omnipotence* is prima facie compatible with giving up omnipotence).

1. Possibly, there is an omnipotent being.
2. Necessarily, if x is omnipotent, then x exists at @.
3. Necessarily, any omnipotent being is essentially omnipotent*.
4. Therefore, there is an essentially omnipotent* being.

Premises (2) and (3) need support. First, necessarily, a being is only omnipotent if it could create me (directly or mediately). But by essentiality of origins I could be created by a being only if I am created by the being. Therefore, if there is a being that could create me, that being creates me at @, and hence exists at @. Thus, (2). Also, plausibly, an omnipotent being could be the First Cause in any possible world. Hence, an omnipotent being must be a necessary being, and hence exist at @. Thus, (2).
What about (3)? Well, an omnipotent being could exercise its omnipotence to put itself in any state possible to it. Suppose it's possible for an omnipotent being to fail to be omnipotent*. Then the omnipotent being could make itself be non-omnipotent* by exercising its omnipotence. But then the being would be omnipotent at some explanatory point in that world where it makes itself non-omnipotent*, and hence it would be omnipotent* there. So absurdity arises. So it's not possible for an omnipotent being to fail to be omnipotent*.

Argument 3:
Say that x knows* p iff x knows p or knows some proposition of which p is a conjunct.

1. Possibly, there is a being x such that for any proposition p that could be true, x could know p.
2. Therefore let w be a world and x a being such that x exists at w and for any proposition p, if p could be true, x could know p.
3. Therefore, if w* is any possible world and p be any proposition true at w*, then x could know that w* is actual and p.
4. x could know that w* is actual and p only at w*.
5. Therefore, if w* is a possible world and p is true at w*, then x exists at w* and knows* that p at w*.
6. Therefore, there is a being that exists at every world and knows* every truth at every world.