Part of a set of free teaching resources called "Encouraging Critical Thinking Online" by Meriel Patrick of Oxford University, written for the Intute Virtual Training Suite <http: />

1. Encouraging Critical
Thinking Online
Unit 1
Checking Facts and
Gathering Opinions

2. How many Christians are there in
the world today?
• Find three websites that provide an
answer
• Fill in the boxes on the worksheet
for each of them
• Comment on any notable features
of the sites or answers you discover

3. How many Christians are there in
the world today?
• It’s virtually impossible to arrive at
an exact figure, so any answer will
be an estimate
– Though some sources may not
explicitly acknowledge this
• Estimates will differ for a variety of
reasons

4. How many Christians are there in
the world today?
• Estimates may vary in precision
– The first hit for a Google search for “
How many Christians?” gives an
answer of ‘more than one billion’
– This isn’t wrong, but it’s easy to find
estimates for more than twice this
number

5. Results of Google search for
‘how many Christians’
Retrieved 6 June 2008

6. Results of Google search for
‘how many Christians’
Retrieved 6 June 2008

7. How many Christians are there in
the world today?
• Other first page hits give higher
figures
– Wikipedia says there are ‘between 1.5
billion and 2.1 billion’
– Adherents.com suggests 2.1 billion, or
about 33% of the world’s population

8. Extract from Wikipedia article on
Christianity
http://en.wikipedia.org/wiki/Christianity Retrieved 5 June 2009

9. Extract from Wikipedia article on
Christianity
http://en.wikipedia.org/wiki/Christianity Retrieved 5 June 2009

10. Adherents.com’s figures
http://www.adherents.com/Religions_By_Adherents.html Retrieved 6 June 2008

11. Adherents.com’s figures
http://www.adherents.com/Religions_By_Adherents.html Retrieved 6 June 2008

12. How many Christians are there in
the world today?
• The Wikipedia article has notes
which show where the figures were
taken from
– A key source is Adherents.com
– So these two sites shouldn’t be cited
as independent sources of the same
figure

13. How many Christians are there in
the world today?
• Figures may vary because of different
methods of calculation – but websites
rarely give full information about this
• Some figures may be more up to date
than others
• Another Adherents.com page gives a
wide range of possible figures

14. How many Christians are there in
the world today?
• The answer will also vary depending on
the definition of ‘Christian’ used
– ReligiousTolerance.org lists a number of
possible criteria
– An article from the Christian Century notes a
wide disparity between those self-identifying
as Christian and those who go to church

15. Extract from ReligiousTolerance.org
http://www.religioustolerance.org/chr_defn.htm Retrieved 8 August 2008

16. Extract from a Christian Century article
on FindArticles.com
http://findarticles.com/p/articles/mi_m1058/is_5_120/ai_98754720 Retrieved 8 August 2008

17. Extract from a Christian Century article
on FindArticles.com
http://findarticles.com/p/articles/mi_m1058/is_5_120/ai_98754720 Retrieved 8 August 2008

18. Summary - key things to note
• Answers may vary because of
– Variations in precision
– Different calculation methods
– Variations in how recently the
information was gathered
• Important terms need to be defined

19. Why might we find conflicting
answers to a question?
• There may be real uncertainty
about the answer
• Authorities may disagree
• There may be multiple ways of
interpreting a question

20. Why might we find conflicting
answers to a question?
• Some sources may be more up to
date than others
• Answers may vary in precision
• Some sources may simply be
wrong

21. Questions to ask when
assessing sources
• Who is the author?
– An individual or an institution?
– What are the author’s credentials?
• Is this a scholarly resource, or a
more informal one?
• How up to date is this source?

22. Questions to ask when
assessing sources
• Are there reasons to doubt the
reliability of this source?
– Does it include information I know to
be false?
– Does it contradict itself or use poor
reasoning?
– Is it biased towards a particular view?

23. Questions to ask when
assessing sources
• Is the information provided
confirmed by other sources?
– Are references provided?
– Do other websites agree? (A major
advantage of the Web is that many
sources can be compared quickly and
easily.)

24. Remember the three Ws
• WHO wrote this site?
– Is the author a trustworthy source?
• WHEN was it written?
– Is it up to date?
• WHY was it written?
– Does the author have an axe to grind?

25. This slideshow is part of
Encouraging Critical Thinking Online,
a set of free teaching resources
designed to develop
students’ analytic abilities,
using the Web as source material.
For the full set, please visit
Intute Training:
http://www.intute.ac.uk/training/