Support A survey published in a leading medical journal in the early 1970s found that the more frequently people engaged in aerobic exercise, the lower their risk of lung disease tended to be. █████ █████ ███████ ████ █████████ █████ ████████ ██ ████ ██ ███ ████ ████ ███████ ████████ ███ █ ███████████ ██████████ ██████ ██ ████████ ███████
The author concludes that aerobic exercise leads to decreased risk of lung disease. Her premises are:
(1) A 1970s survey wherein the more frequently people engaged in aerobic exercise, the lower their risk of lung disease tended to be.
(2) Subsequent surveys yielded the same finding.
This is a “correlation doesn’t imply causation” flaw, where the author sees a correlation and concludes that one thing causes the other without ruling out the two alternatives hypotheses:
(1) The causal relationship could be reversed—people at lower risk of lung disease might gravitate toward aerobic exercise. Maybe healthy lungs make aerobics more fun!
(2) Some other factor could be causing the correlation—maybe something else (maybe living somewhere with good air quality?) causes people to both do aerobic exercise and be at lower risk for lung disease.
The reasoning above is questionable ███████ ███ ████████
ignores anecdotal evidence ███ █████ ███ ██████████ ████████ ██ ██████████ ████████
considers only surveys █████████ ██ ███ ██████████ ███████ ███████
concludes merely from ███ ████ ████ ███ ██████ ███ ██████████ ████ ███ ██████ ███ █████
presumes, without providing ██████████████ ████ ██████ ███ ████ ███ ████ ████ ███████ ██ ██ ████ ██████
fails to consider ████ ████ ██████████ ███████ ████████ ███ ████ ████ ██████████ ██████ ██ ████████ ██████