Does the post hoc fallacy affect the legitimacy of prayer?

Questions about God, the Bible and the Christian culture

Question: How should we as Christians respond to the post hoc ergo propter hoc fallacy when it comes to prayer… and especially when it gets in the way of faith?

Answer: Greetings friend. Thank you for touching down with us at Mainsail Ministries — and thank you for asking such an honest (and probing) question.

I, too, spend many hours pondering the cause-and-effect relationship between a creature like me (one that has free will) and a being like God (one who is omniscient and omnipotent, among other things)… wondering if I am applying energy to affect things that would just happen anyway.

Now, you did not give me any details on how you feel this fallacy might impact your faith. So, I am going to take a guess rather than return your question for clarification. And since my answer will be based on that guess, don’t be afraid to re-query if the answer does not help you.

The post hoc ergo propter hoc fallacy (usually shortened to “post hoc”) challenges the notion that the order of events necessarily indicates cause. So, although it is necessary for a cause to occur before an effect, it is not necessarily true that first phenomena cause second phenomena. But if you think about it, most phenomena are only related incidentally by time. So, most have no cause-and-effect relationships between them.

The fallacy states that A occurred, then B occurred... and that therefore, A caused B. But that logic breaks down pretty quickly when people assert things like "the rooster crowed immediately before sunrise; therefore the rooster caused the sunrise." This is funny when it comes to roosters… but people — and this includes Christians — make this kind of mistake all the time. So, what does the post hoc fallacy have to do with prayer?

If God, who is omniscient, already knows what I’m going to pray about, then why should I bother praying at all? Wouldn’t that be a waste of time — especially in the light of the post hoc fallacy which tells us that latter events are not necessarily tied to former events in a cause-and-effect way? So, how could I prove to anyone (including myself) that prayer worked when post hoc opens the door to a prayer and a healing being just incidentally related?

Let’s say that you prayed for someone to get well... and they did get well. Could you claim that this occurred necessarily because of your prayer? I wish I could say, yes — and every time! But there is almost no way to tell whether this is true. In fact, one of God’s great provisions argues against it being true: God built our bodies to heal themselves, and I don’t hear many Christians complaining about this.

But the data provided by this provision shows that self-healing is the norm… and this means that God-healing isn’t the norm. Now, this doesn’t prove that God does not heal in response to prayer. All this says is, when God heals specifically, it’s a special case… and I think that this tracks more with how the Bible shows God working, and I think it tracks more with our Christian experience, too.

In my world, the fact that our bodies heal themselves is God’s way of answering my prayer before I pray it! But for non-believers (and especially for those who are philosophical materialists), the post hoc fallacy says that there is no necessary link between a Christian’s prayer and subsequent healing. They would say, people pray all the time… and people get well all the time whether or not people are praying for them — and I concur. There is no necessary link.

It’s natural for Christians who understand the post hoc fallacy and who understand that God knows and can affect the future to ask, why bother praying at all? … and if I’m reading you correctly, this is where you are. But this logical “pickle” helps us clarify the role of prayer in a believer’s life… because we now know there are two things we are not doing when we pray.

First, we are not giving God information (… him being omniscient and all that). Second, it would be folly to go all Word-Faith on him — insisting that he jumps through the hoops of a formulaic prayer-and-response paradigm. So, if we are not informing him or “testing” our faith by worldly gain, what are we doing?

For one thing, we are obeying God. God tells us to pray (2 Chronicles 7:14; Psalm 102:17; Jeremiah 29:12; Matthew 5:44; Romans 8:6; 12:12; James 5:13). So, until Jesus comes back, we must at least pray as a matter of obedience. There’s more to it, of course… but there’s at least that.

Second, it’s not reasonable to assume that we will always see the effect of our prayers. So, we should not rely on cause-and-effect-style feedback to validate prayer. We pray in obedience, and we pray in faith.

Third — and I’m working on the assumption that we want what God wants — we should encourage God in his work. Jesus told a parable about a persistent widow who kept badgering the judge for justice (Luke 18:1-8) … the lesson being that God wants us to petition him for things like justice, too… even though we know it’s ultimately coming. God is the judge and the redresser of wrongs… and there’s nothing wrong with cheering him on.

Fourth, the post hoc fallacy only challenges the notion that precedence necessarily equals cause. It does not weigh-in on whether or not prayer is answered, so there is no actual problem for a Christian here. Prayer is just as it always was: some subscribe to its efficacy and some don’t… and the post hoc objection stands… and God’s word stands… yet these are all true at the same time.

Prayer isn’t about cause-and-effect anyway… although prayers of intercession (and even imprecation!) have their place. It is about fellowship with God — communing with him — as you would with the most intimate friend (Genesis 5:22-24; James 4:8). God does not want to do parlor tricks for us — jumping through the hoops of our requests. Mainly, he just wants to hang out with us — and no... I can’t figure that out either.

I pray this has helped you.

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