Cooperation is crucial.
Quotes to consider:
“The only thing that will redeem mankind is cooperation.” – Bertrand Russell
“Leadership is based on inspiration, not domination; on cooperation, not intimidation.” – William Arthur Ward
“It is through cooperation, rather than conflict, that your greatest successes will be derived.” – Unknown
“We are all dependent on one another, every soul of us on earth.” – George Bernard Shaw
“Now join your hands, and with your hands your hearts.” – William Shakespeare