Some online sources attribute the expression that “it is better to light a candle than to curse the darkness” to Eleanor Roosevelt, when in fact it was said ABOUT her, by Adlai Stevenson at her memorial service.
The book is intended to explain the scientific method to laymen, and to encourage people to learn critical or skeptical thinking. It explains methods to help distinguish between ideas that are considered valid science, and ideas that can be considered pseudoscience. Sagan states that when new ideas are offered for consideration, they should be tested by means of skeptical thinking, and should stand up to rigorous questioning.
Sagan presents a set of tools for skeptical thinking which he calls the “baloney detection kit”. Skeptical thinking consists both of constructing a reasoned argument and recognizing a fallacious or fraudulent one. In order to identify a fallacious argument, Sagan suggests the employment of such tools as independent confirmation of facts, quantification and the use of Occam’s razor. Sagan’s “baloney detection kit” also provides tools for detecting “the most common fallacies of logic and rhetoric”, such as argument from authority and statistics of small numbers. Through these tools, Sagan argues the benefits of a critical mind and the self-correcting nature of science can take place.
The phrase appears originally to be a Chinese proverb, perhaps by Confucius.
A lightbulb joke is a joke that asks how many people of a certain group are needed to change a light bulb. Generally, the punch line answer highlights a stereotype of the target group. There are numerous versions of the lightbulb joke satirizing a wide range of cultures, beliefs and occupations.
The original formulation of the joke was used to insult the intelligence of the (often ethnically defined) target group:
Q. How many [members of the target group] does it take to change a light bulb?
A. Ten — one to hold the light bulb and nine to turn the ladder around.
Most variations follow this scheme:
Q. How many [insert target group here] does it take to change a light bulb?
A. N — one to replace the light bulb and N-1 to [behave in a fashion generally associated with a negative stereotype of that group].
Often the stereotypical behavior will involve elaborate decision-making processes, and/or Byzantine management and supervision of the bulb-changing. The actual bulb changer may be last in the list for extra punch, especially when following a long recital of various supporting roles, each employing more [members of the target group] than the previous one.
Although lightbulb jokes tend to be derogatory in tone, the people targeted by them may take pride in the stereotypes expressed and are often themselves the jokes’ originators. Lightbulb jokes applied to subgroups can be used to ease tensions.