Module 9 Flashcards
The conclusion of an inference to the best explanation is supposed to explain an observation in one of the premises
“True.”
What is inferred as the conclusion in an inference to the best explanation is supposed to best explain the observation that needs to be explained in the premises. For example, if someone argues “This meat smells very bad, so it must be spoiled”, then what is inferred is the hypothesis that the meat is spoiled, and that hypothesis is supposed to explain why the meat smells bad, as the premise says.
Inferences to the best explanation are deductive.
“False.”
Inferences to the best explanation are invalid and defeasible, as we saw in the previous two Questions. That makes them inductive rather than deductive.
Inferences to the best explanation are intended to be valid.
The correct answer is “False.”
Even if a hypothesis is the best explanation of an observation, it is still possible that the hypothesis is false. For example, even if the hypothesis that Vijeth killed the victim is the best explanation that we can imagine of why his fingerprints were on the glass (see Question 2 in this exercise), it still might be true that he is innocent and his fingerprints were planted on the glass by the person who really killed the victim. Thus, it is possible for the premises to be true and the conclusion false in an inference to the best explanation. That makes such arguments invalid.
Inferences to the best explanation are defeasible.
“True.”
Even if a hypothesis is the best explanation of what has been observed so far, future additional evidence might make the inference weak. For example, even if the hypothesis that this chemical kills that kind of bacteria is the best explanation that we can imagine right now of why the bacteria died (see Question 3 in this exercise), we might later find out that a lab assistant spilled soap into the dish, and the soap rather than the other chemical might be what killed the bacteria. This additional information about the spilled soap then defeats the strength of the inference to the best explanation. Thus, such arguments are defeasible.
If two competing explanations of the same event are equally good, then we can use an inference to the best explanation to justify belief in one of those explanations.
The correct answer is “False.
In order to justify the conclusion of an inference to the best explanation, that conclusion must be better than any competing explanation. If two explanations are equally good, neither of them is better than the other, so neither is best. Thus, if two competing explanations are equally good, then we cannot use an inference to the best explanation to justify belief in either of them as opposed to the other. Instead, this comparison cannot tell us which of them is correct.
The purpose of an inference to the best explanation is to justify its conclusion.
“True.”
Inferences to the best explanation are based on explanations, but their goal or purpose is not to explain what was observed but, instead, to justify belief in the hypothesis that best explains what was observed. In the example in the lecture, when I observe that water is falling on my head, I infer that there must be a leak in the roof, because that is the best explanation of why I observe what I do—namely, that water is falling on my head. This inference is supposed to justify belief in the conclusion that there is a leak in the roof.
Scientists use inference to the best explanation to draw conclusions from observations in their experiments.
“True.”
After scientists perform experiments and get results, they need to determine which hypothesis about what happened in the experiment best explains why they got the results that they got. For example, suppose a scientist adds a chemical to a group of live bacteria and then observes that the bacteria are dead an hour later. The scientist infers that the best explanation of why the bacteria died is that the chemical killed those bacteria. That inference provides some reason to believe that this chemical kills that kind of bacteria.
Inferences to the best explanation include a premise about an observation that needs to be explained.
Inferences to the best explanation include a premise about an observation that needs to be explained.
“True.”
An inference to the best explanation must postulate an explanation of something, so it must include a premise about something that needs to be explained (as discussed in the lecture). For example, if someone argues “This meat smells very bad, so it must be spoiled”, then the premise that the meat smells very bad is what needs to be explained.
Detectives use inference to the best explanation to solve murder mysteries.
“True.”
After gathering evidence (such as fingerprints, footprints, blood samples, eyewitness reports, and so on), detectives need to determine which hypothesis about who committed the crime best explains why they found the evidence that they found. For example, if the best explanation of why Vijeth’s fingerprints were on the glass at the crime scene is that Vijeth was there during the crime, and if there is no explanation of why Vijeth would be there then unless he was there to kill the victim, then that provides some reason to believe that Vijeth killed the victim.
One premise in an inference to the best explanation claims that one explanation is better than others.
The correct answer is “True.”
If someone claims only that a hypothesis would explain something, then we cannot infer that that explanation is correct, because another conflicting explanation might also explain that event just as well or even better. For example, if the claim that Jamshed committed the murder would explain the eyewitness testimony, but the claim that Jamshed’s twin brother committed the murder also would explain the eyewitness testimony, then we cannot tell whether it was Jamshed or his twin brother who committed the murder. That is why an inference to the best explanation must be an inference to the best explanation. In order to claim that an explanation is the best, the inference needs a premise (possibly suppressed) that the explanation in its conclusion is better than any alternative explanation.
