By the end of this lecture you should be able to: Understand the value of the “Socratic Method” Understand the role and importance of skepticism Compare and contrast opinions and arguments Evaluate the types, strengths and limitations of the evidence available Compare and contrast the value of primary sources and secondary sources  

1. Critical Thinking and the Use of Evidence
Professor Joel Hayward

2. By the end of this lecture you should be able to:
• Understand the value of the “Socratic Method”
• Compare and contrast opinions and arguments
• Evaluate the types, strengths and limitations of the evidence
available

3. People may be of equal worth, but their assertions are not
There are weak and strong assertions
Weak assertions:
 Are based on incomplete information
 Contain flawed logic
 Ignore, minimize or exaggerate facts because of bias
 or are not adequately based on evidence

4. The Socratic Method
Socrates 470 – 399 BCE

5. ἔλεγχος (Elenchus) = disproof, refutation, cross examination
• Step-by-step challenging or disproving of premises
• A cooperative argumentative dialogue between individuals, based on
asking and answering questions to draw out increasingly deeper truths
• Achieved through revealing and eliminating the error, contradiction or
incompleteness of statements

6. Example:
Statement: A fish is an animal that swims
Q: “A dog swims. So is a dog a fish?”
A. No. A fish lives in the water and swims.
Q: “An alligator lives in the water and swims. So is an alligator a fish?”
A. No. A fish lives and swims and breathes in the water.
Q: “An octopus lives and swims and breathes in the water. So is it a fish?”
A. No. A fish lives and swims and breathes in water and has a backbone.
An octopus has no backbone.

7. This is not rhetoric (persuasion through skillful oratory)
Not debate (not proving your position)
The best Socratic statements to prompt deeper thinking:
• “Why do you believe that?”
• “Explain what you mean by it”
• “What assumptions make you think that?”
• “How strong is the evidence for that?”
• “Explain what caused that”

8. Skepticism

9. Question / doubt everything
Hasan ibn al-Haytham (“Alhazen”), Basra, 965 – c. 1040 CE
“Skepticism [‫]الشك‬ should drive all useful inquiry.”

10. “Truth is sought for its own sake ... A seeker of truth is not the person
who studies the books of his predecessors and allows his own
worldview to influence how he understands them.
“But rather the person who is thinking about them and is filled with
doubts ... who follows proof and demonstration rather than the
assertion of a man whose natural disposition is characterized by all
kind of defects and shortcomings ....
A person who studies, if knowing the truth is his goal, should turn
himself into a hostile critic of everything that he studies ... and he will
attack it from every side. He should also suspect himself as he
performs his critical examination of it. If he takes this course, the truth
will be revealed to him along with any flaws”.
— Hasan Ibn al-Haytham, Shukuk ‛ala Batleemus (
‫بطليموس‬ ‫على‬ ‫شكوك‬
)
(“Doubts on Ptolemy”) Cairo: National Library Press, 1971, p. 37

11. Objectivity
The state of not being influenced by emotions, personal tastes or preferences
or personal, cultural or national bias

12. Bias
A pattern of deviation from the way your mind ordinarily forms judgments,
whereby inferences may be created unreasonably
Confirmation bias is the tendency to search for, interpret, favor, and recall
information in a way that confirms one’s existing beliefs while giving
disproportionately less attention to information that contradicts it
Halo effect
Seeing one aspect of a person, organization or entity so positive that we see all
or most other things about it positively

13. Vantage Point / Viewpoint

15. Description versus Explanation

16. Description:
Who, what, when, where, how?
Explanation:
Why?
What caused it?
What were / are the consequences?
Narrating or chronicling
what happened
Demonstrating why
things happened the way
they did and what
impact or consequences
they had

17. Analysis involves both DESCRIPTION and EXPLANATION
At Master’s Level the ratio greatly favors explanation
EXPLANATION
DESCRIPTION

18. Description vs Explanation
On 1 September 1939, the German Army and Air Force attacked
Poland and defeated the Polish military within six weeks. The
German military was better equipped than its Polish
counterpart and used superior tactics in support of a
encirclement strategy.

19. Description vs Explanation
On 1 September 1939, the German Army and Air Force attacked
Poland because of Hitler’s obsessive desire for strategic
Lebensraum (living space). Catching Poland by surprise before it
could sufficiently strengthen its defenses in critical sectors,
Germany defeated the Polish military within six weeks. Having
devoted considerable resources and adopted an experimental
approach to weapons and tactics, the German military was
better equipped than its Polish counterpart. It had more tanks
and monoplane aircraft, and used superior tactics, including the
revolutionary integration of armored columns and close air
support, in support of a encirclement strategy.

20. Evidence

21. HUMAN ACTIVITIES
give rise to
MYTHS
and unsound
explanations

22. SOURCES
HUMAN ACTIVITIES
give rise to
MYTHS
and unsound
explanations
but also leave

23. SCHOLARS
SOURCES
MYTHS
and unsound
explanations

24. apply rationality, judgment,
objectivity and an analytical
method to the
SCHOLARS
SOURCES
MYTHS
and unsound
explanations
to challenge

25. apply rationality, judgment,
objectivity and an analytical
method to the
and produce a coherent
understanding of the
intentions, actions and
consequences that we might
accept as truth
SCHOLARS
SOURCES
MYTHS
and unsound
explanations
to challenge

26. Primary sources: sources originating only from participants in events
Versus
Secondary sources: sources originating from subsequent or uninvolved scholars,
observers, and commentators

27. Key primary sources include:
• Documents of record (treaties, minutes
of meetings, official reports, directives,
war diaries, registers of births and
deaths, census records, church or
mosque records, etc.)
• Correspondence (letters, emails etc.)
• Diaries, journals, memoirs
Mainly in
archives

28. Key secondary sources include:
• Books by scholars
• Scholarly journal articles
• Newspapers and magazines
• Encyclopedias
• Retrospective reports by ministries, authorities, and other
organizations
You will
mainly use
these

29. Scholars believe that their works are only “true” until new sources or
new interpretations of existing sources appear
Constantly revising knowledge is therefore considered normal and
advantageous
All sources contain biases because they are the product of humans
The only way to escape bias is strenuously to maintain “critical
distance” (i.e. objectivity)
Sources are always incomplete
Some general principles regarding sources:

32. • Is it authentic?
• Who produced it?
• What was his or her status or role?
• What was influencing him or her at the time?
• Why was it produced?
• Who is its intended readers?
• What biases might it reflect?
• What its author in a position to know?
The “interrogation” of sources:

33. Of all primary sources, those based on memory (memoirs, autobiographies, and
interviews) are definitely considered the least reliable
Why is that?
• They originate after the events
• Even the best memory is both faulty and malleable
• Blame-shifting occurs
• Credit-taking occurs
• External influence occurs

35. “Wie bisher werden aber wiederum keine
ganzen entschlüsse gefaẞt. Es is, also ob
der Führer dazu nicht mehr fähig wäre.”
(“As usual, no bold decisions are taken. It is
as though the Führer is no longer capable
of making any decisions at all.”)
—Kriegstagebuch des OKW: Eine
Dokumentation, 21 December 1942, Band
2, Teilband 2, p. 1168
Published versions of unpublished primary sources?

36. “Kiss me, Hardy” vs. “Kismet, Hardy”
Trafalgar, 21 October 1805

37. Bayeux Tapestry, 70 meters x 50 cm (c. 1076 CE)

38. Antoine Lancelot’s
engraving (1733)

40. Logic
Deductive Reasoning
All cats have fleas
I have a cat
Therefore: my cat has fleas
Conclusion: Certain (if all premises are
correct)

41. Logic
Inductive Reasoning
I observed that my cat has green eyes
I observed that another cat has green eyes
Hypothesis: All cats have green eyes
Experiment: Observe the eye color of cats
everywhere
Conclusion: Tentative

42. Kalam Cosmological Argument of Ibn Rushd
All things that begin to exist have a cause
The universe began to exist
Therefore: the universe had a cause
Ibn Rushid (‫رشد‬ ‫)ابن‬
1126 – 1198
“Averroes”

43. Ordinarily, the closer a source is to
the time of the event, the more
reliable it is considered
Θουκυδίδης

44. Γίνεται δὲ κατὰ τοῦτον τὸν χρόνον Ἰησοῦς σοφὸς ἀνήρ, εἴγε
ἄνδρα αὐτὸν λέγειν χρή: ἦν γὰρ παραδόξων ἔργων ποιητής,
διδάσκαλος ἀνθρώπων τῶν ἡδονῇ τἀληθῆ δεχομένων, καὶ
πολλοὺς μὲν Ἰουδαίους, πολλοὺς δὲ καὶ τοῦ Ἑλληνικοῦ
ἐπηγάγετο: ὁ χριστὸς οὗτος ἦν. καὶ αὐτὸν ἐνδείξει τῶν πρώτων
ἀνδρῶν παρ᾽ ἡμῖν σταυρῷ ἐπιτετιμηκότος Πιλάτου οὐκ
ἐπαύσαντο οἱ τὸ πρῶτον ἀγαπήσαντες: ἐφάνη γὰρ αὐτοῖς τρίτην
ἔχων ἡμέραν πάλιν ζῶν τῶν θείων προφητῶν ταῦτά τε καὶ ἄλλα
μυρία περὶ αὐτοῦ θαυμάσια εἰρηκότων. εἰς ἔτι τε νῦν τῶν
Χριστιανῶν ἀπὸ τοῦδε ὠνομασμένον οὐκ ἐπέλιπε τὸ φῦλον.
About this time there lived Jesus, a wise man, if indeed one ought
to call him a man. For he was one who performed surprising
deeds and was a teacher of such people as accept the truth
gladly. He won over many Jews and many of the Greeks. He was
the Christ. And when, upon the accusation of the principal men
among us, Pilate had condemned him to a cross, those who had
first come to love him did not cease. He appeared to them
spending a third day restored to life, for the prophets of God had
foretold these things and a thousand other marvels about him.
And the tribe of the Christians, so called after him, has still to this
day not disappeared.
Josephus served Vespasian
and Titus
Earliest Greek manuscripts
10th to 11th Centuries CE
C. 250 Origen says Josephus
did not believe that Jesus was
the Jewish Messiah
c. 330 Eusebius of Caesarea
first to quote the passage in
Ἐκκλησιαστικὴ ἱστορία
Arab historian Agapius
(Mahbūb ibn-Quṣṭanṭin)
quotes a version that differs
from that of Eusebius.
C. 93 Flavius Josephus,
Antiquities of the Jews,
Book 18, Chapter 3, 3

45. A
Paris suppl. graecus 255 (once the Cisalpinus or
Italicus)
11-12th c.
B Vatican gr. 126. Parchment 11th c.
C Florence, Laurentian 69, 2. Parchment. 11
E Heidelberg library, Palatinus 252. Parchment. 11
F Munich, Augustanus 430. Parchment. 11
G Munich gr. 228. Paper. 13
M British Library 11727. Parchment. 11
Thucydides’s History of the Peloponnesian War was completed by c. 415 BCE.
The text was first printed in Venice in 1502 CE (i.e. 1917 years later)
These divide into two families, CG and ABEF. C and B are the best in each family. M is
mid-way between the two families. We do have Papyrus Oxyrhynchus 16 and 17, but
these are very slender and date from 500 years and 700 years after Thucydides lived.

46. SOPHOCLES (496-406 BCE): 11th century CE
PLATO (427-347 BCE.): 9th century CE
ARISTOTLE (384-322 BCE): 10th/11th century CE
HERODOTUS (c. 480-425 BCE): 10th century CE
JULIUS CAESAR (100-44 BCE): 9th century CE (the best MSS
of the bellum Gallicum stem from 11th/12th century.)
TACITUS (fl. 100 CE): All writings descend from a codex of
10th century CE, found in 1455, now lost except for eight
pages, the remainder known through 15th century copies.

48. • Archaeology and geographical field work
Yarmouk 636: Umar (Khalid ibn al-Waleed) and Islamic Army vs.
Heraclius (Theodore Trithyrius) and Byzantine Army

49. ‫بدر‬ ‫غزوة‬
624
‫الخندق‬ ‫غزوة‬
627

50. 628 ‫خيبر‬ ‫غزوة‬

51. Stalingrad 1942-1943

55. Concluding thoughts
Remember that a good arguments requires:
 Logical inferences leading from valid premises to a conclusion
 As much objectivity as you can manage at every stage of the thinking
process
 As much evidence as one can reasonably obtain and interrogate

56. Thank you