# Difference between correlation/causation and post hoc ergo propter hoc

• Simfish
In summary, the two fallacies are not equivalent. One ignores time on the left side, while the other accounts for time.f

#### Simfish

Gold Member
Correlation <=> Causation and post hoc ergo propter hoc fallacy

The difference is that the latter implies a temporal element, whereas correlation <=> causation doesn't always imply a temporal element. On the other hand, does every action have to take a time? After all, a causation must take time. So while one can conceive of a situation where the two expressions are not equivalent; are the two expressions are equivalent in our world?

Correlation <=> Causation and post hoc ergo propter hoc fallacy

The difference is that the latter implies a temporal element, whereas correlation <=> causation doesn't always imply a temporal element.

...which makes them similar yet slightly different fallacies.

On the other hand, does every action have to take a time?

Any action involves a change (the terms are somewhat synonymous) and any change takes time (the concepts are somewhat equivalent) so yes, every action takes time.

So while one can conceive of a situation where the two expressions are not equivalent; are the two expressions are equivalent in our world?

You've answered your question. The first fallacy ignores time on the left side therefore it is different from the second fallacy which does account for time. Also, "our world" is the only one that counts, imaginary worlds are not relevant.

"Correlation <=> Causation"

Correlation does not necessarily cause an action. For instance fire will not burn without the presence of oxygen, fuel and heat. neither Oxygen nor fuel cause the fire to burn but there is a Correlation of 1 (one) to their presence and fire. Heat may cause a fire to burn but only in the presence of oxygen AND fuel.

Therefore: "Correlation <=> Causation" does not hold in our world or universe.

Correlation <=> Causation and post hoc ergo propter hoc fallacy

The difference is that the latter implies a temporal element, whereas correlation <=> causation doesn't always imply a temporal element.
No! - just because one event comes after another, that doesn't necessarily mean the first event caused the second one. That's the main fallacy.

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Royce and Russ: isn't the question about the DIFFERENCE between both fallacies? (Simfishy will correct me if I misunderstood.)

Yeah, out of whack perfectly clarified my question. Thanks. :)

Oh, ok - yeah, the second is just a special case of the first.

Okay, now I've thought about it and changed.

While the logical truths "correlation does not imply causation" and "post hoc does not imply procter hoc" are logically equivalent, the two fallacies are not equivalent.

Event A can be concurrent with Event B. Thus, it is impossible that Event A can cause Event B. However, it does not stop a person H from invoking fallacy A, while steering clear of fallacy B. H may not understand logic, but H at least is able to make one fallacy while steering clear of the other.

It seems that a lot of conspiracy theories suffer from this. But maybe not => since conspiracy theories trace both events to a common cause (but clearly indicate that while event A and event B may have a common cause, they do not in turn cause one another).

InKryption