Summarize Argument
The educator concludes that the educational programs teaching parents to be their child's "first teacher" are successful and should be expanded. He supports this by pointing out that children in these programs perform better than average in school.
Notable Assumptions
The educator assumes that the educational program directly causes the better school performance, without considering other possible reasons for it, like the natural abilities of the children or parents, or parental involvement outside the program.
He also assumes that better than average school performance is the primary marker of the program’s successfulness, without considering any other outcomes or effects among the children in the program.
He also assumes that better than average school performance is the primary marker of the program’s successfulness, without considering any other outcomes or effects among the children in the program.
A
Not all small children enjoy being taught by their parents.
The school performance of children in the program is better than average, whether they enjoy the program or not, and (A) doesn’t account for this difference. So (A) doesn’t weaken the conclusion that the program is successful and should therefore be expanded.
B
Most of the parents participating in the programs have prior experience as educators.
This weakens the conclusion by showing that one of the educator’s assumptions is false. He assumes that the program itself causes the children’s good performance, but (B) explains that their performance could actually be due to most of the parents having experience as educators.
C
Surveys show that most parents would approve expanding the programs.
The school performance of children in the program is better than average, whether parents approve of the program or not, and (C) doesn’t account for this difference. So (C) doesn’t weaken the conclusion that the program is successful and should therefore be expanded.
D
The cost of expanding the programs has not been precisely determined.
First, we don’t know that this means that the program will be expensive. Perhaps the cost hasn’t been determined but it will be quite low. But either way, (D) doesn’t account for the children’s school performance and thus doesn’t weaken the conclusion.
E
Some children who did not participate in the programs performed exceptionally well in school.
Just because some children who didn’t participate in the program performed well in school doesn’t mean that the program is unsuccessful. The children in the program still performed better than average. So (E) doesn’t weaken the educator’s conclusion.
Summarize Argument
The researcher concludes the study does not support recommending North Americans eat fewer calories to extend their lives. Why not? Because unnaturally calorific laboratory diets are the reason a reduced-calorie diet increased longevity in the study.
Notable Assumptions
The researcher assumes that North Americans’ diets are more in line with their natural calorie intake than the diets of laboratory animals. Furthermore, she assumes the animals studied had a pre-diet calorie intake typical for laboratory animals.
A
North Americans, on average, consume a higher number of calories than the optimal number of calories for a human diet.
This challenges the assumption that the laboratory animals’ unnaturally high calorie intake makes them dissimilar from North Americans. If North Americans consume more calories than optimal, then they are similar to laboratory animals in that way, not different.
B
North Americans with high-fat, low-calorie diets generally have a shorter life expectancy than North Americans with low-fat, low-calorie diets.
This relationship between fat intake and life expectancy does not imply that the study’s findings can be correctly extended to North Americans. The researcher does not say fat intake was examined separately from calorie intake.
C
Not all scientific results that have important implications for human health are based on studies of laboratory animals.
This states that some studies with implications for human health do not involve laboratory animals, not that studies of laboratory animals must or usually have implications for human health.
D
Some North Americans who follow reduced-calorie diets are long-lived.
This does not say North Americans who eat fewer calories are tend to live longer—it’s possible North Americans on normal diets are more likely to be long-lived than those on reduced-calorie diets.
E
There is a strong correlation between diet and longevity in some species of animals.
This does not specify which type of diet increases longevity or identify the species in question. This may support doctors making some dietary recommendation to increase longevity, but not the one described on the basis of the study.