I love analogies. When explaining a new concept to someone, analogies can be the shortest path towards understanding.
On the other hand, I've often ran into people who will completely dismiss what I'm saying because they've found a "fault" in the analogy. They'll say, "that's a faulty analogy fallacy", and then that's it - no attempt to address the point you've made.
Incidentally, "faulty analogy fallacy" ins't a real thing. All analogies are faulty, but that's not actually an issue.
Here's what analogies aren't
An analogy is not evidence. It is not an argument.
While "faulty analogy fallacy" isn't real, "argument from analogy" is. In short, arguing from an analogy is when you subjectively place A and B into the same category, then declare that an arbitrary attribute of A is also shared with B.
For example, here's one atheists get a lot:
- DNA is a kind of code.
- All the other code we know of is written by an intelligence.
- Therefore, DNA is written by an intelligence.
It'd be like saying,
- Horses are a kind of vehicle (something we use to carry ourselves, or our stuff around).
- All the other vehicles we know about were created by humans.
- Therefore, horses were created by humans.
It doesn't work. Maybe humans did manufacture horses completely from scratch - but it doesn't follow from this argument. You'd be right for the wrong reasons.
As I said, though, an analogy isn't about trying to prove a point (when they're done right).
Here's what analogies are
An analogy is communication. It's about taking something you already understand, "copy-and-paste" it, and modify the copy... so it can be a template for this new thing you're trying to grasp.
For example, let's try this. You don't know what "promelgranpyrminating" is. What is it? "promelgranpyrminating" is when you go surf-boarding, except, instead of a surfboard, you're riding a clown... and instead of water, it's lava.
Now you know. You knew what surfing was, and we've used that concept to springboard you into understanding a new concept. I didn't even have to explain what I mean by "riding", or mention waves, because you're already familiar. All that information is imported from the previous concept.
That doesn't make it real, though. Nor does it prove anything. The purpose is to get you understanding a concept, whether it's right or wrong.
Why all analogies are fallacious
They're all fallacious because they're never exact matches. Back to the person who dismisses your analogy on a bizarre technicality, suppose you had this conversation:
- I say, "Evolution doesn't require lineages to be constantly changing. The adaption is like a cup of coffee in a room. As the coffee cools, it's rate of cooling slows, until it reaches equilibrium with the room."
- Creationist says, "That's faulty analogy fallacy. Animals aren't made of ceramic."
That's basically true (maybe there's some creature out there that has ceramic-like materials), but that doesn't - in any way - invalidate what I'm trying to communicate. The point is that evolutionary change is generally proportional to how well the species is already adapted to its environment (loosely put). I'm just trying to get the creationist to grasp the concept based on something else he/she already understands.
Ultimately, the person is just throwing out a red herring - trying to distract from the point. The only way to satisfy this person would be to compare the concept to itself, achieving 100% exactness:
- "Evolutionary change is proportional to how well adapted the species is to the environment, like how in evolution, evolutionary change is proportional to how well adapted the species is to the environment."
At this point, it's just a tautology. Of course, even if I'm successful at communicating the concept, my next task would be to demonstrate it, if that's my goal.
I love analogies. It's just frustrating to try to explain something to someone who's not listening, except to correct my grammar at every turn, insisting that every grammatical error proves that I'm factually incorrect.