There is an actual fallacy in formal logic usually labeled something like “wishful thinking.” This is when someone either accepts a claim, or urges acceptance of a claim based solely on the fact that it would be great if it were true. Now, most times this is a lot more subtle in nature than stating the phrase outright (“wouldn’t it be great if…”), and is used by some of the best public speakers. There is a subtle manipulation of emotion involved and it is more of an appeal to that emotion than to any type of actual logic or reality.
Now, why is this a topic for the Christian Scribbler? I actually see this in a lot of apologetics for non-scripturally backed “Christian” religion. What I mean by this is that a true Christian that studies the scriptures, and believes them, are a lot less likely to fall pray to this particular fallacy. As an example there are some people who profess Christ that believe that God is like a cosmic Genie who is bound to answer every request…wouldn’t that be nice? Wouldn’t that be the way God would operate in an ideal world?
At best, this approach is a misapplication of scripture, at worst it is idolatry; forming God into an image instead of learning of God Himself, how He really is, NOT how we would “like” Him to be or “wish” Him to be. I see this amongst most non-believers as well. They paint pictures of God as they wish to see Him, and then reject those pictures; you see “wishful thinking” can work the other way as well….”Wouldn’t it be great if this wasn’t true!?” So it can apply to the rejection of claims too (again, it is a lot more subtle than this, but you get the point). This can go hand-in-hand with the straw man fallacy.
One of the other areas I see this in is the idea of Christ alone as the approach to God. Meaning there is this undercurrent of “wouldn’t it be great if Christ wasn’t the only way to God, and all religions actually wind up taking people to God?” The sad thing is, is that I see this amongst people that claim to be Christian. The fallacy is that wishing it does not make it true. Truth is all about reality. With God, the fallacy of wishful thinking is even more dangerous; it elevates what we think would be best over God’s plan that is absolutely the best, since it springs from a perfect mind that has perfect power, including perfect love. We should trust what God reveals over our own opinion about what would be “best,” for the evidence abounds that He can indeed be trusted in every circumstance to work it out to His perfect plan in His perfect timing, which winds up being best for humanity.
The reminder is this; don’t let sentimentality or wishful thinking blur truth, and just because we want something to be true doesn’t mean it is. What we find in objective Truth is actually more wonderful, more “freeing” than anything we could ever come up with on our own. One last thing, this fallacy is not the same thing as hope. Hope is not a logical fallacy, hope accepts the truth, accepts reality, and it also trusts, and expects good. Hope makes us stronger, whereas the logical fallacy of wishful thinking actually weakens us, and our positions, because it is not based in truth.