Partial Cause and Multi-Cause Scenarios

[mmcdermott]

I recently purchased the Logical Reasoning Bible and while reviewing Chapter 8 I found myself a bit confused on Partial Cause and Multi-Cause section. I know that for probable and possible causes giving an alternate cause, showing cause w/o effect, or showing effect w/o cause would not be effective in weakening the conclusion; but, how would you weaken a partial-cause or multi-cause conclusion.

Obviously, providing an alternate cause wouldn’t be effective because the stimulus is pointing out that there is more than one cause of the effect; so, would you weaken the conclusion just like a possible/probable cause conclusion?

Thanks in advance for any clarification provided!

[Jeremy Press]

Hi mmcdermott,

When dealing with multi-cause conclusions, if the language of the conclusion is certain, then you can use the normal "alternate cause" method to Weaken the argument. The example the Bible gives is: "It was a lack of attention on the part of the driver and bad luck that caused the accident." Here, the author is certain these are (without anything more) the two causes of the accident. Thus, showing another cause of the accident would weaken the conclusion.

But, when dealing with partial-cause conclusions, as well as multi-cause conclusions worded in less certain ways (e.g., "Lack of attention on the part of the driver and bad luck both played a role in the accident, among other factors"), the conclusion is much less subject to attack. The likelihood with such conclusions is that they'll be used in questions other than Weaken questions. The only real way to Weaken such conclusions is to find an answer showing (or suggesting) that the posited partial cause (or one of the multiple causes) was NOT (or could NOT have been) a cause of the effect. Using the example above, an answer showing that, just before the accident, the driver was not distracted would weaken the conclusion.

I hope this helps!

Jeremy