Tuesday, November 15, 2011

Question about Feasibility

This article will be a little more basic, but it has some practical applications. Recently, a question was posed to me concerning possibility and feasibility, and whether there really is a difference between the two. Something is logically possible if it is not self-contradictory (call this the “coherence test”) and if it does not violate any necessary truths (propositions, events, or beings that are impossible to be “false”). Something is feasible, however, in the case that what is under consideration can be done or true. So feasibility is more circumstances oriented.

Here’s a brief example. It’s logically possible for me to fly, but since I cannot fly, it’s not really feasible for me to fly. Similarly, for God, simply because something is possible it does not follow that it is feasible. The principle can be expressed like this: everything that is feasible is also possible, but not everything that is possible is feasible.

So in the case of God’s creating people and his free choice to allow his creatures (mankind) to have a free will, God cedes causal control of a person’s actions to the person. So while it is possible a created person may choose to be saved, it nonetheless may not be feasible for God to guarantee this, because there just is no circumstance in which that person chooses that way! Or perhaps, less controversially, there are circumstances in which certain persons would believe if they were placed in them, but the truths of how other people must act in order for these certain persons to believe and be saved make this infeasible for God to instantiate.[1]

In order for God to instantiate the world, he must actualize a world where all of the relevant propositions are consistent with each other (call this “compossibility”). Thus, if it is true only in circumstances C1 would Randy freely ask Jodi to marry him, it is infeasible for God to create C2 and yet have Randy freely ask Jodi to marry him (at least as long as God allows freedom). Yet it is still logically possible Randy freely asks Jodi to marry him in C2. It’s just not feasible given truths of how he would act. Does that make sense? What say you?

                [1] Again, it must be stressed here that we are not saying God cannot simply force everyone to do something. What we are saying is that because God sovereignly chose to give man a free will, certain truths of the way people act are not directly and completely up to God.

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  1. "It’s logically possible for me to fly, but since I cannot fly..."

    I don't get it. How is it logically possible for you to do something you can't do?

    1. There's nothing contradictory about the idea of a man flying. We can conceive of this in our minds because this isn't logically contradictory. Think of the Superman movies for example. However, it isn't physically possible for a man to fly. It's logically possible, but not actually impossible.

    2. Right, Evan! As I said below in my original response to Ryan, the only problem with saying "it is logically possible for me to do something I cannot do" is if the "cannot" is in the logical sense; but of course, I don't think the "cannot" is in a logical sense, thus there is no problem.

  2. Hi Ryan. :) By "cannot" in the relevant sentence, I am describing mere laws of physics, or more precisely, that I lack the aerodynamic appendages or parts to enable me to fly. But since it's not a logical requirement that I lack these things (it is neither a necessary truth that I do nor is it something that is essential to being a person), we have a case where there is a logical possibility, yet I can't really do it.


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