Final answer:
The key point of Watson's human caring science grand theory is to recognize the importance of human-to-human environmental and ecological associations and value the subjective experience of both individuals and nurses.
Step-by-step explanation:
The key point to Watson's human caring science grand theory is to recognize that human-to-human environmental and ecological associations are important and value the subjective experience of both individuals and nurses. Watson's theory emphasizes the significance of the caring relationship between the nurse and the patient, acknowledging the importance of the patient's subjective experience and the holistic approach to care. This theory promotes the practice of nursing in a wholly respectful way, guiding nurses to move toward desired outcomes from the client perspective. It also highlights the preservation of the integrity of human beings through self-care.