Outline of Plato's contrast of knowledge and opinion in the Meno 
  1. Knowledge is a mental faculty/power that allows us to apprehend "being" (i.e., reality).

  2. Ignorance is the opposite of knowledge.

    Conclusion from 1 & 2:
  3. Opinion is subject to error, but knowledge is not.

    Conclusion from 2 & 3:
  4. Opinion differs from  knowledge

  5. Different faculties involve different "spheres" (areas they govern).

    Conclusion from1 & 5:
  6. Opinion involves a different faculty, and has a different subject-matter.

  7. Particular objects are subject to "opposite names." 
    For example: The same house is beautiful to one person, ugly to another, and the same person is at one time young, at another time old.

    Conclusion from 6 & 7:
  8. Particulars are in the region between being and not-being.

    Conclusion from 6 & 8:
  9. Particulars are the subject-matter of opinion.

    Conclusion from 3, 6, & 9:
  10. Eternal and immutable natures are the subject-matte of knowledge.