Comparisons help the reader to
understand concepts by drawing
parallels between an unknown and a
Figure of speech comparing two things
(without using ‘like’ or ‘as’)
• “Dr. Love […] claims that scientists have found the
glue that holds society together” (Crockett).
Compares oxytocin to ‘glue’ to illustrate oxytocin’s
supposed role in human empathy and bonding
• “The most evident bridge between morality and
religion is the idea of virtue” (Murdoch 363).
Compares ‘virtue’ to a ‘bridge’ in order to illustrate the
idea that virtue connects morality and religion; both
morality and religion share concepts of virtue
Figure of speech using ‘like’ or ‘as’ to
compare two things
• “Who is the center of the wedding solar system? The
bride. She had the biggest increase in oxytocin. […]
Her mother was number two.Then the groom's
father, then the groom, then the family, then the
friends -- arrayed around the bride like planets
around the Sun” (Zak).
Compares wedding attendants to ‘planets around the Sun’
in order to illustrate the central role of the bride and thus
her relationship to oxytocin levels
Gives his example extra impact and flare with the added
solar system imagery
Extended comparisons often used to
argue that if two things are alike in one
way, they are alike in other ways as well
Argument from analogy
• Doesn’t state that two things are identical, only
• Strength of argument depends upon factors such
as the examples used in the analogy, the
relevance of the similarities, and the number of
shared characteristics between the examples
• “[H]ow therefore can there be an objective notion of
well-being? Well, consider by analogy, the concept
of physical health. The concept of physical health is
undefined. […] Notice that the fact that the concept
of health is open, genuinely open for revision, does
not make it vacuous” (Harris).
• “[W]hy wouldn’t this undermine an objective
morality? Well think of how we talk about food […]
There is clearly a range of materials that constitute
healthy food. But there’s nevertheless a clear
distinction between food and poison. The fact that
there are many right answers to the question, ‘What
is food?’ does not tempt us to say that there are no
truths to be known about human nutrition” (Harris).
Arguments from analogy can be refuted
• Disanalogy: Arguing that the two compared
items have many relevant dissimilarities
• Counteranalogy: Counterargument related to
• Unintended consequences: Stating that the
analogy leads to conclusions that undermine the
Watchmaker analogy: “It is ridiculous to assume that
a complex object, like a watch, came about randomly.
Therefore, one must assume that a complex object,
like the universe, must have an intelligent designer in
the form of God.”
Philosopher David Hume refutes watchmaker
• Disanalogy: A watch and the universe have many
dissimilarities; for instance, the universe can be disorderly and
• Counteranalogy: Some natural objects (like snowflakes) also
have order and complexity but are not the result of intelligent
• Unintended consequences: Complex objects, such as watches,
result from the labor of many individuals; thus the watchmaker
analogy unintentionally implies polytheism.
(“Argument from analogy”)
“[W]hy wouldn’t this undermine an objective morality? Well think
of how we talk about food […] There is clearly a range of materials
that constitute healthy food. But there’s nevertheless a clear
distinction between food and poison. The fact that there are many
right answers to the question, ‘What is food?’ does not tempt us to
say that there are no truths to be known about human nutrition”
Refuting Sam Harris’ morality-food analogy:
• Disanalogy: Morality and food have many dissimilarities; morality
relates to the mind and philosophy, while food deals with the
physical, so the two cannot be compared.
• Counteranalogy: Many poisons are used in medicine, and thus
can be considered ‘healthy.’
• Unintended consequences: Many people experience allergic
reactions to certain foods, so what may be healthy food for one
person may be detrimental to another. Similarly, what may be
moral for one person may be immoral to another person.
Therefore, comparing morality to food unintentionally supports
the view of moral relativism.
“Argument from Analogy.” Wikipedia. Wikimedia Foundation, 23
Oct. 2014. Web. 19 Dec. 2014.
Crockett, Molly. “Beware Neuro-bunk.” TEDSalon. Unicorn Theatre,
London, England, UK. 07 Nov. 2012. Conference Presentation.
Harris, Sam. “Science Can Answer Moral Questions.” TED. Long
Beach Performing Arts Center, Long Beach, CA, USA. 11 Feb 2010.
Lunsford, Andrea A., John J. Ruszkiewicz, and Keith Walters.
Everything’s an Argument with Readings. 6th
ed. New York:
Bedford/St. Martin’s, 2013. Print.
Murdoch, Iris. “Morality and Religion.” AWorld of Ideas: Essential
Readings for CollegeWriters. 9th
ed. Ed. Lee A. Jacobus. New York:
Bedford/St. Martin’s, 2013. 358-71. Print.
Zak, Paul. “Trust, Morality – and Oxytocin?” TEDGlobal. Edinburgh
International Conference Center, Edinburgh, Scotland, UK. 14 Jul.
2011. Conference Presentation.
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