Fidelity to the subject's thought and to his characteristic way of expressing himself is the sine qua non of journalistic quotation.
Marriage is the most obvious public practice about which information is readily available. When combined with the traditional Jewish concern for continuity and self-preservation - itself only intensified by the memory of the Holocaust - marriage becomes the sine qua non of social membership in the modern Orthodox community.
For me, politeness is a sine qua non of civilization.
A practical way to travel between the stars is a must-have for space opera, and a sine qua non for our frequently vaunted future as a galactic society.
Taking charge of your own learning is a part of taking charge of your life, which is the sine qua non in becoming an integrated person.
Sound money is the sine qua non of a prosperous society.
Winning the Revolutionary War, or the Civil War, or World War II were the turning points in our history, the sine qua non of our forward progress.
A clear lesson of history is that a 'sine qua non' for sustained economic recovery following a financial crisis is a thoroughgoing repair of the financial system.
Mysticism, in the narrow sense, implies a specific experience which is foreign to most poets and most men, but on the other hand, it represents an instinct which is a human sine qua non.