Home Introduction to Logic
Introduction to Logic
SOME VERY COMMON LOGICAL FALLACIES PDF Print E-mail
Written by Calvin Fox   
Friday, 07 February 2014 16:40

BEWARE OF LOGICAL FALLACIES in media reporting, on Blogs and in opinion columns

  • Equivocation – the misleading use of a term with more than one meaning (by glossing over which meaning is intended at a particular time).
  • Ecological fallacy – inferences about the nature of specific individuals are based solely upon aggregate statistics collected for the group to which those individuals belong.
  • Etymological fallacy – which reasons that the original or historical meaning of a word or phrase is necessarily similar to its actual present-day meaning.
  • Fallacy of many questions – someone asks a question that presupposes something that has not been proven or accepted by all the people involved.
  • Fallacy of the single cause (oversimplification) – it is assumed that there is one, simple cause of an outcome when in reality it may have been caused by a number of only jointly sufficient causes.
  • False attribution – an advocate appeals to an irrelevant, unqualified, unidentified, biased or fabricated source in support of an argument.
  • Fallacy of quoting out of context – refers to the selective excerpting of words from their original context in a way that distorts the source's intended meaning.
  • False authority (single authority) – using an expert of dubious credentials and/or using only one opinion to sell a product or idea. Related to the appeal to authority fallacy.
  • Hedging – using words with ambiguous meanings, then changing the meaning of them later.
  • Historian's fallacy – occurs when one assumes that decision makers of the past viewed events from the same perspective and having the same information as those subsequently analyzing the decision.
  • Fallacy of composition – assuming that something true of part of a whole must also be true of the whole.
  • Fallacy of division – assuming that something true of a thing must also be true of all or some of its parts

Note: These common fallacies are not original with me, but I gathered and adapted them from several sources.

 

Share
Last Updated on Saturday, 08 February 2014 08:53
 
The Rejection of Rationality and Reason PDF Print E-mail
Written by Calvin Fox   
Wednesday, 31 August 2011 13:27

The classic view that rationality is a major characteristic of the Image of God is properly derived from the Doctrine of Creation and what it reveals about God.  Rationality, Logic, Principles of Mathematics are all derived from Theology- the nature of God Himself.  However, today’s culture values the non-rational, even as it de-values God

“In the late nineteenth and early twentieth centuries there were important movements in the arts,the sciences and the social sciences that, taken together, represent a significant revision of modern  thought. What is known as Postmodernity arose out of a rejection of the Enlightenment’s key point, the primacy of rationality.” - p.199

Material in this Article is adapted from HISTORY THROUGH THE EYES OF FAITH by Ronald A Wells.  “One of the deep currents in the twentieth century is non-rationalism, by which we do not mean irrationalism but a conscious rejection of the faculty of human reason as the highest state of human endeavor and the best avenue toward truth.”

Share
Read more...
 
Introduction to Basic Logic PDF Print E-mail
Written by Calvin Fox   
Monday, 04 August 2008 15:11
God has a mind- Romans 11:34 "who has known the mind of the Lord"

God thinks- Isaiah 55:9 as the heavens are higher than the earth, so are ... my thoughts than (yours)

God does not have a physical brain. His mind and thoughts do not require neurons and chemistry.

Logical thinking or rational discourse presupposes and requires certain Rule or Laws of Thought:
  • Identity (A is A)
  • Contradiction (A can not be Not A at the same time and place)
  • Excluded Middle (A or Not A)

"The Law of Contradiction is a presupposition and non-negotiable principle for Christian Theology and Apologetics." "Without [logic] no knowledge of anything cognitive can be achieved." "The basic Law of rational intelligibility (is) the Law of Contradiction." - R.C. Sproul

Secular Philosophers agree-

"denial of [the 3 Laws] would make all discourse impossible." "Without assuming the Law, [no one could] assert anything, not even a denial of the Law itself"- Hospers

"any system to be workable at all must be governed by some principle of consistency" - A.J Ayer

NOTE: these Laws of Aristotelian Logic do not apply to nonsense statements ["there are no absolutes" or "This statement is false"] or to self-reference statements ["the square root of 4 is asleep" or "Zeus is insane"]

Share
Last Updated on Tuesday, 17 March 2009 11:41
Read more...