You ask the following: What are the values which you (I) consider one must have? Let me start by saying that an answer to your question depends on what kind of persons we are (e.g., prosocial, antisocial, religious, non-religious, moral orientation) and the culture or social milieu in which we live. As for this, it suffices to say that anthropologist Richard Shweder has spoken about the big three of morality: Autonomy and its focus on individual rights. Community and its emphasis on one's duties to the community or the group, Divinity and its stress on the divine law.
As you certainly know, the moral or ethical value and even principle of autonomy pervades the majority of Western societies; the moral or ethical value and even principle of community pervades the majority of Eastern societies; and the moral or ethical value and even principle of divinity pervades the majority of highly religious countries. As I see it, my answer to your question takes into account three main ethics:The ethic of justice, whose main injunction is that we should not treat others and even ourselves unfairly (see, for this respect, L. Kohlberg's theory of moral development); the ethic of care, whose main injunction is that we should not turn away from someone in need (e.g., physical, psychological, spiritual) (see, for this respect, C. Gilligan's thinking on her ethic of caring and responsibility) and the ethic of conservation whose main injunction is that we should protect nature (e,g,, not to pollute water, air, or earth) not only because it is useful for us, but also because it deserves to be respected in itself (see, for this respect, P. Kahn's work on environmental values. In this vein, I think that to respect ourselves, others, and nature are three fundamental values one must have. When this is the case, we can say that we live in harmony with ourselves, the others, and nature and hence are making a little contribution to the cosmic harmony or order that seems, say, to govern the universe.
As I see it, his harmony is related to one's pursuit of truth, goodness and beauty. Note that the true, the good and the beautiful are universal categories, regardless of how they are seen at different times and places, Accordingly, to be committed to the true, the good, and the beautiful are also, I think, three main values one must have.
If I were to make a list of the main values one must have the list would be the following. As these values are intertwined, their order in the list is not operative.
(1) to live in harmony with, and respect, ourselves,
(2) to live in harmony with, and respect, the others,
(3) to live in harmony with, and respect, nature,
(4) to be committed to the true,
(5) to be committed to the good,
(6) to be committed to the beautiful.
I could say that these six values that I think one must have also represent, so to speak, ethical principles, that is, prescriptive and reversible moral principles that should be followed at all times and places.
I think a distinction should be made between the "must-have" values mentioned by Arun and the personal universal values identified by the Schwartz Theory on Human Values as mentioned by Claudia.
The first, the "must-have values", depend on moral and ethical systems which differ depending on every culture as well as on personal constructions of value systems that each of us produces as a result of the interaction between our culture's input and our genetics.
The second, the universal values, constitute a pattern of value system that Professor Schwartz has evidenced through his investigations with transcultural samples in more than 80 countries during the last three decades. This pattern presents a list of values that, with reasonable differences, generally constitute the main motivational domains in western societies.