All people have different characteristics of the nervous processes in the body, a combination of mobility and poise, emotionality and restraint. These are innate qualities that affect the ability of people to communicate with each other, the choice of profession, social activity, which are a manifestation of four types of temperament: choleric, sanguine, phlegmatic, melancholic. In their pure form, such types of temperament are rare, in most of those around you you will find a mixed temperament with a predominance of a strong or weak type of the nervous system, poise and imbalance, greater and lesser mobility of nervous reactions.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.