Take, for instance, the human family. In the absence of cooperation and understanding, parents and children are always fighting. The same is true of quarrels between couples. Divorce ensues and no peace or happiness remains. The marriage is ruined.
Cooperation is imperative for a healthy family, body, society and nation.
Voluntary actions, altruism and showing concern for the welfare and rights of others. For example, if you are concerned about other people and genuinely friendly toward them, then other people will also respond appropriately. I love smiles and laughter. If one wants more smiles in one's life, one must create the right conditions for it. There are many different kinds of smiles.