Principles are those fundamental truths or beliefs that constitute and serve as the foundation for a person's belief systems and ways of living. They are the moral values and virtues that an individual believes, adheres to and works towards achieving it. It constitute the very essence of how a person wants to live his/ her life. and attempts to live accordingly in addition towards making the world a better place.
In the given sentence, the correct spelling for the word to be put in the blank space is principles.
I think that the answer that your are looking at is Principles which are desirable norms, rules or values of a person or group of peopleThey are essential in the construction of people´s behaviour.
