In Japan, Korea, and to a less extent in a few other countries some people believe in a connection between a person’s blood type and their personality. There is no scientific basis for this belief but it still persists.

An essay on May 2021 TOK Essay Prescribed Title #6 needs to investigate how bias plays a positive and negative role in the pursuit of knowledge.

Consider possible biases in this RLE:

  • People believing / not believing in the theory because of how they feel about the traits associated with their blood type
  • People believing in the theory because they trust someone who believes in it
  • People not believing in the theory because they trust someone who does not believe in it
  • The role of bias in popular publications about the blood type theory
  • The role of bias in scientific publications about the blood type theory
  • How the blood type theory has affected some people in the workplace
  • How the blood type theory has affected some people’s personal lives