Illusion: When Appearances Deceive

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Course Description

We think we see the world around us as it is. Sometimes, however, things are not as they appear. We see a straight stick in the water as bent, or are taken in by a vivid dream or hallucination, or treat as reliable a source that turns out to peddle fake news. How do these various illusions impact our efforts to learn from experience? What strategies can we adopt—as individuals, as researchers, and as citizens—to combat these sorts of error? And what happens when things go right, when our senses teach us how the world really is? This course will explore these and similar questions concerning illusions in their many forms, drawing on resources past and present from philosophy, psychology, neuroscience, and the sociology of science.

Course Objectives

This course aims to help students:

  1. Gain an appreciation for the various forms perceptual error and their significance for our cognitive lives;
  2. Come to understand the cultural and historical influences shaping our notions of illusion, perception, and reality; and
  3. Think freely and critically about how these issues affect them as individuals, researchers, and citizens.

Learning Outcomes

By the end of the course, the successful student will have demonstrated the ability to:

  • express philosophical ideas clearly, both verbally and in writing;
  • read and critically assess philosophical and other academic literature;
  • identify the elements of an argument and assess it for soundness and validity; and
  • apply these skills to novel cases.

The key to success in this course is to keep up with the assigned readings and to attend and participate regularly in class activities.

If you keep up with the lectures and readings you will not be assigned anything for which you are unprepared!

Course Components

Each student’s success in meeting these objectives will be assessed on the following bases:

  • Students will be expected to write two term tests covering the major ideas presented in class, as well as two term papers responding in-depth to questions prompted by course readings.
  • Additionally, student attendance and class participation will be assessed on the basis of reading response questions given out on the third meeting of each unit, which will be devoted to class discussion and group activities. Students may opt out of reading responses with no penalty only once; with the exception of University excused absences, which must be supported by official documentation, students must complete all other reading responses and attend all other class meetings.
  • Finally, on discussion days students will be assessed for their participation in class discussion and group activities.


Final grades will be determined according to the following rubrics:

Assignment % of Final Grade
Term Paper 1 15%
Term Paper 2 25%
Term Test 1 20%
Term Test 2 25%
Participation 15%
Total 100%
You must complete all assignments in order to pass the course!

Grading Scale

Score Grade Performance
96–100 A+ Surpasses All Grading Criteria
90–95 A Satisfies All Grading Criteria; No Errors
87–89 A- Satisfies All Grading Criteria; At Least One Minor Error
83–86 B+ Satisfies Most Grading Criteria; Minor Errors
80–82 B Satisfies Most Grading Criteria; Perhaps Some Major Errors
77–79 B- Satisfies Most Grading Criteria; One or More Major Errors
73–76 C+ Satisfies Some Grading Criteria; Some Major Errors
70–72 C Satisfies Some Grading Criteria; Several Major Errors
67–69 C- Satisfies Some Grading Criteria; Many Major Errors
64–66 D+ Satisfies Almost No Grading Criteria; At Least One Fatal Error
60–63 D Satisfies Almost No Grading Criteria; One or More Fatal Errors
0–59 F Satisfies No Grading Criteria, Incomplete, or Plagiarized
Final grades are rounded up from the 2nd decimal place; no exceptions will be made.

Texts & Course Materials

Required Texts

There are no required texts for this course. All required readings will be posted to Blackboard.

Additional Materials

Students looking for additional study materials are encouraged to consult the Stanford Encyclopedia of Philosophy.

Course Policies

Disabilities and Different Styles of Learning

Education is a pluralistic enterprise: there are several and often incompatible styles of learning. If you believe there is an alternative approach to this material that would better suit your style of learning, do not hesitate to bring it up with me. If you have a disability for which you are or may be requesting accommodation, you are encouraged to contact both me and the Office of Disability Services at 0 (212) 338 10 42 as early as possible in the term. ODS will verify your disability and determine reasonable accommodations for this course.

Academic Honesty

The goal of this course is to promote and assess your satisfaction of the above-stated course objectives. Cheating not plagiarism will not be tolerated. Students suspected of violating the University’s policy on academic integrity, noted below, will be required to participate in the required procedural process as initiated by the instructor. A minimum sanction of a zero score for the quiz, exam, or paper will be imposed.

Be sure you are familiar with KU’s complete policy on academic honesty, which is available in the Student Code of Conduct

Email Policy

Allow me two business days to respond to emails. Please do not email me with questions of philosophical substance—that is what lecture, discussion, and office hours are for—and please consult this syllabus before asking questions about course policy.