In the article the author discusses peculiarities of three areas of psychologists’ professional activity: conducting scientific research, educating new generations of psychologists, and having a private practice. He particularly stresses the significance of empirical testability of theories for correct and ethical assessment practice (according to Evidence-Based Assessment standard) and therapeutic practice (according to Evidence-Based Practice in Psychology standard). The author also explores the cultural immersion of psychological activity.
The paper is dedicated to the memory of Professor Jan Strelau, who passed away in Warsaw 4th of August 2020. Professor Jan Strelau was the most prominent and world-wide recognized Polish psychologist and his scientific contribution was essential for psychology of individual differences and studies on temperament. Paper presents the life and scientific achievements of Professor Jan Strelau.