Abstract

Human psychological differences are typically divided into two distinct categories: cognitive abilities and personality traits. The present article focuses on cognitive abilities. First, the key aspects of measuring human cognitive differences will be explained. This will be followed by a brief overview of the associations between cognitive ability scores and several variables relevant in the medical context. Measurement of cognitive ability is a transparent and objective procedure. The meaningfulness of the procedure can be assessed in a simple and clear way: cognitive ability scores are worthwhile numbers if they can predict important outcomes such as socioeconomic success, longevity,  health and health-related behaviours in the manner or to the extent that other variables cannot do. It will be shown that cognitive ability, indeed, predicts longevity, presence of various diseases and health risks, and people’s ability to take care of their health. It will be discussed that human cognitive differences may explain the general and paradoxical relationship between socioeconomic opportunities and health. It appears that even if health-related information and medical care are equally available to all, not everyone can equally benefit from them – differences in cognitive ability may be the very reason for this. The article will end with several suggestions aiming to alleviate this problem.