Course:Phil150/inductivearguments

An argument where the truth of the premises does not guarantee the truth of the conclusion, though the premises do provide support for the conclusion’s probable truth. Inductive arguments usually rest on a hidden premise, that the future will be like the past (this is sometimes called the principle of uniformity of nature).

Example of an inductive argument: 1. The sun has risen every day in the past (as long as the Earth has been around, anyways) C. The sun will rise tomorrow

Some factors that affect the strength of inductive arguments are sample size (how many known instances are you relying on) and bias (are all the known instances you are relying on adequately representative of the population you are trying to make inferences about).

Example of weak inductive argument due to small sample size:

A man moves to Vancouver during the middle of winter. He is from a country located near the equator where there's is very negligible variance of daylight between summer and winter solstice After about a week in Vancouver he notices it gets dark at around 5 every night. With this information he comes up with the weak inductive argument that it always gets dark in Vancouver around 5 o'clock.

1. It has been getting dark in Vancouver at around 5pm every night for the past week C. Therefore, it always gets dark in Vancouver at around 5pm

This is a weak inductive argument because a week is too small a sample size to come up with the conclusion that it gets dark nightly at 5 o'clock, because as we know as the year changes so too does the time of sunset and sunrise.

Example of weak inductive argument due to biased sample: (Stephanie Leung)

According to the enrolment statistics for 2016, 64% of Arts Undergraduate students were female. Therefore, there are more female students enrolled at UBC than male students.

>This is a weak inductive argument due to biased sample, as the statistics from just the faculty of Arts is not representative of all of UBC. (Not to mention how students choose to identity may not land on a gender-binary)

Example of argument from analogy:

1. Machines are complex systems with intricate parts 2. Humans are complex systems with intricate parts 3. Machines are produced by an intelligent designer 4. Therefore, humans are probably the product of an intelligent designer too

A factor that affects the strength of arguments from analogy is how relevant the known similarities between the two objects or classes or comparison are to the similarity inferred in the conclusion.

Examples of weak arguments from analogy, where the known similarities are largely irrelevant to the similarity inferred in the conclusion:

1. I wear pants and shoes, and also like chocolate 2. you wear pants and shoes 3. so you probably also like chocolate

1. unhealthy foods have the property of not being liked by Kim Kardashian 2. broccoli has the property of not being liked by Kim Kardashian 3. therefore, broccoli is probably an unhealthy food