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- Intro to logic
- Propositional logic
- Exercises for propositional
Problems on propositional logic,
including truth-tables, boolean algebra, and inference rules.
Please write logic formulas using the syntax
previously defined ,
using
(or for brevity,
F
),
(or
T
),
¬, ∧, ∨, and ⇒.Except where directed, use only these connectives.
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Propositional logic
[Practice problem
solution provided.]
Your friend Tracy argues:
It is bad to be depressed.
Watching the news makes me feel depressed.Thus, it's good to avoid watching the news.
Regardless of whether the premises and conclusion are true,
show that the
argument is not,
by showing it doesn't hold for all domains.Replace
depressed
and
watching news
with
expressions which leave the premises true,but the conclusion false
(or at least, what most reasonable people would consider false).
Lots of possible counterexamples.
It is bad to be depressed.
Doing homework makes me depressed;so it's good to not do my homework.
Or,
It is bad for people to be in physical pain.
Childbirth causes pain.Therefore childbirth needs be avoided by all people.
If the original conclusion is really correct,
Tracy needs to elucidate some of his unspoken assumptions.
The flaw seems to be along the lines of,
avoiding bad in the short run
may not always be good in the long run
(or equivalently, sometimes you have to
choose the lesser of two evils).No, you weren't asked to name a specific flaw,
and reasonable people can differ on precisely what the flaw is.(And, formal logic is not particularly helpful here.)
Nonetheless, uncovering hidden assumptionsin arguments often helps understand the real issues involved.
For fun,
pick up the front page of the daily newspaper,and see how many arguments use faulty rules of inference and/or
rely on unspoken premises (which not all might agree with).In particular, political issues as spun to the mainstream press
are often riddled with error,even though there are usually reasonable arguments on
both sides which policy-makers and courts debate.
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[Practice problem
solution provided.]
An acquaintance says the following to you:
Chris claims knowledge is more important than grades.
But she spent yesterday doing an extra-credit assignmentwhich she already knew how to do.
Therefore, she's a hypocrite and deserves no respect.
Regardless of whether the premises and conclusion are true,show that the
argument is not,
by showing it doesn't hold for all domains.Replace
knowledge
and
grades
with expressions which
give you true premises, but a false conclusion(or at least, what most reasonable people would consider false).
Exaggerate
knowledge
to something more important,
and
grades
to something less important.
Terry claims that encouraging human-rights
is more important than playing Tetris.But Terry played Tetris yesterday
rather than volunteering with
Amnesty International .
Most people wouldn't condemn Terry as a hypocrite just
because of this; even the most dedicated of people areentitled to
some free time.
If your friend wants to prove Terry hypocritical,they'll have to provide further evidence or arguments.
Or similarly,
Politician X
claims to support science funding,
but voted against a proposal to shift all Medicare funds to NASA.
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Questions & Answers
Discuss the differences between taste and flavor, including how other sensory inputs contribute to our perception of flavor.
taste refers to your understanding of the flavor . while flavor one The other hand is refers to sort of just a blend things.
Faith
While taste primarily relies on our taste buds, flavor involves a complex interplay between taste and aroma
Kamara
which drugs can we use for ulcers
Omeprazole
Cimetidine / Tagament
For the complicated once ulcer - kit
Patrick
what is the function of lymphatic system
to drain extracellular fluid all over the body.
asegid
The lymphatic system plays several crucial roles in the human body, functioning as a key component of the immune system and contributing to the maintenance of fluid balance. Its main functions include:
1. Immune Response: The lymphatic system produces and transports lymphocytes, which are a type of
asegid
to transport fluids fats proteins and lymphocytes to the blood stream as lymph
Adama
Anatomy is the identification and description of the structures of living things
Kamara
what's the difference between anatomy and physiology
Anatomy is the study of the structure of the body, while physiology is the study of the function of the body. Anatomy looks at the body's organs and systems, while physiology looks at how those organs and systems work together to keep the body functioning.
AI-Robot
what is enzymes all about?
Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems
Kamara
how does the stomach protect itself from the damaging effects of HCl
little girl okay how does the stomach protect itself from the damaging effect of HCL
Wulku
it is because of the enzyme that the stomach produce that help the stomach from the damaging effect of HCL
Kamara
function of digestive system
function of digestive
Ali
what is the normal body temperature
please why 37 degree selcius normal temperature
Mark
the normal temperature is 37°c or 98.6 °Fahrenheit is important for maintaining the homeostasis in the body
the body regular this temperature through the process called thermoregulation which involves brain skin muscle and other organ working together to maintain stable internal temperature
Stephanie
anaemia is the decrease in RBC count hemoglobin count and PVC count
Eniola
what is the pH of the vagina
how does Lysin attack pathogens
Diya
I information on anatomy position and digestive system and there enzyme
anatomy of the female external genitalia
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Source:
OpenStax, Intro to logic. OpenStax CNX. Jan 29, 2008 Download for free at http://cnx.org/content/col10154/1.20
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