AN EXPLANATION OF INDUCTIVE AND DEDUCTIVE REASONING
I believe that Inductive logic leads to the most errors and mistakes that are commonly made by most people. An example of this would be the great Sherlock Holmes per Critical Thinking, (Possin, K 2002).
"Even one of the greatest critical thinkers of all time, Sherlock Holmes, was totally screwed up about the deductive-inductive distinction. Where he thought he was "deducing" conclusions on the basis of his observations, he was in fact making inductive inferences." So if Sherlock Holmes was mistaken about his induction inferences, we must believe that the average person with much less training in critical thinking, could hardly do better.
Deductive reasoning, is using the conclusion of an argument, to make explicit the premise(s). Because of this the conclusion is stating something that is already true from its premise in the argument. In other words, it’s a solved problem.
Inductive arguments are not solved. They use past premises to draw future conclusions; another problem is the claims in the conclusion go beyond the premise. Unfortunately this does not hold up logically, as the variables and information of the past, may be changed in the future, so these same rules may not apply. Thus the claim has gone beyond the premise.
An Example of this would be:
Mice that were caged next to a cellphone, developed higher cancer rates.
Humans using cell phones developed higher cancer rates.
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Cell phones cause cancer
This seems to sound logical, but because it is not logically impossible for new cell phones to change design, radiation emission levels, etc it could not pass as deduction but as induction. The statement also would fail as it takes past events and then switches to future conclusions.
Let’s look at another inductive argument:
More dogs with dark brown color have been found to be female
More Humans with dark brown skin have been found to be female
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Dark brown coloration causes females.
Again this would not pass the deductive test, and probably not the cogent test. Obviously the past statistics showing dark brown colored animals and humans could not be considered deductive,this is because the possibility of another reason to explain the conclusion can easily be found. Diet, Adapting to the environment, species, etc are all valid reasons for the same conclusion.
Summing Up:
Deductive and Inductive arguments are easily confused by the average laymen. Deductive arguments are solved problems, basically the conclusion is reinforcing the premise, and validating it, but the conclusion does not project beyond the premise. Inductive logic uses past information, and speculates on what the future will do. Inductive logic fails the deductive test as it can contain things in its conclusion that are not contained in the premise. We are basically predicting, the future, instead of using deductive logic which shows how the present has been reached. Inductive arguments fool the most people, even the great Sherlock Holmes.
I believe that Inductive logic leads to the most errors and mistakes that are commonly made by most people. An example of this would be the great Sherlock Holmes per Critical Thinking, (Possin, K 2002).
"Even one of the greatest critical thinkers of all time, Sherlock Holmes, was totally screwed up about the deductive-inductive distinction. Where he thought he was "deducing" conclusions on the basis of his observations, he was in fact making inductive inferences." So if Sherlock Holmes was mistaken about his induction inferences, we must believe that the average person with much less training in critical thinking, could hardly do better.
Deductive reasoning, is using the conclusion of an argument, to make explicit the premise(s). Because of this the conclusion is stating something that is already true from its premise in the argument. In other words, it’s a solved problem.
Inductive arguments are not solved. They use past premises to draw future conclusions; another problem is the claims in the conclusion go beyond the premise. Unfortunately this does not hold up logically, as the variables and information of the past, may be changed in the future, so these same rules may not apply. Thus the claim has gone beyond the premise.
An Example of this would be:
Mice that were caged next to a cellphone, developed higher cancer rates.
Humans using cell phones developed higher cancer rates.
-----------------------------------------------------------------------------------------------------------
Cell phones cause cancer
This seems to sound logical, but because it is not logically impossible for new cell phones to change design, radiation emission levels, etc it could not pass as deduction but as induction. The statement also would fail as it takes past events and then switches to future conclusions.
Let’s look at another inductive argument:
More dogs with dark brown color have been found to be female
More Humans with dark brown skin have been found to be female
---------------------------------------------------------------------------------------------------------------------------------------------------------
Dark brown coloration causes females.
Again this would not pass the deductive test, and probably not the cogent test. Obviously the past statistics showing dark brown colored animals and humans could not be considered deductive,this is because the possibility of another reason to explain the conclusion can easily be found. Diet, Adapting to the environment, species, etc are all valid reasons for the same conclusion.
Summing Up:
Deductive and Inductive arguments are easily confused by the average laymen. Deductive arguments are solved problems, basically the conclusion is reinforcing the premise, and validating it, but the conclusion does not project beyond the premise. Inductive logic uses past information, and speculates on what the future will do. Inductive logic fails the deductive test as it can contain things in its conclusion that are not contained in the premise. We are basically predicting, the future, instead of using deductive logic which shows how the present has been reached. Inductive arguments fool the most people, even the great Sherlock Holmes.