In media interviews, Fisher has argued that falling in love depends on both similarity and complementarity XII
Chemistry’s survey and matching process focus more on chemistry than compatibility. The survey has approximately 150 questions, with responses to questions designed to measure four personality types, each associated with a particular hormone or chemical: Explorer (Dopamine), Builder (Serotonin), Director (Testerone), and Negotiator (Estrogen). For example, users are asked in one question to indicate the length of their index finger relative to their ring finger (which can be related to the level of testosterone). In another question, users are asked to recognize sincere versus insincere faces, which Fisher argues is related to estrogen (being a Negotiator) (Gottlieb, 2006).
