verifiability principle

But the qualities Mario Cuomo brought to public life—compassion, integrity, commitment to principle—remain in short supply today.
President Cuomo Would’ve Been a Lion|Jonathan Alter|January 2, 2015|DAILY BEAST
Nixon said defending the two islands was “a matter of principle.”
The World’s Toughest Political Quiz|Jeff Greenfield|December 31, 2014|DAILY BEAST
If the noble experiment of American democracy is to mean anything, it is fidelity to the principle of freedom.
The Sony Hack and America’s Craven Capitulation To Terror|David Keyes|December 19, 2014|DAILY BEAST
Let the record show that espousing principles is common; acting on principle is rare.
Justice Ginsburg Shouldn’t Quit Just Yet|Kevin Bleyer|December 1, 2014|DAILY BEAST

The principle that outsiders should be welcomed and provided for was a cross-cultural theme in ancient cultures.
Pope Bids Refugees to EU ‘Bienvenido’; Europe Says ‘Non’|Candida Moss|November 30, 2014|DAILY BEAST
Many so-called "humming tones" are given for practice, but in accepting them observe whether the foregoing principle is obeyed.
Expressive Voice Culture|Jessie Eldridge Southwick
The grand thing is to have each of your five fingers go "dum, dum," an equal number of times, which is the principle of all three!
Music-Study in Germany|Amy Fay
He had hitherto lived for universal man:—his days should terminate on a different principle.
The Pastor's Fire-side Vol. 3 of 4|Jane Porter
The gauge of railways in Great Britain was not fixed upon any scientific principle.
Fifty Years of Railway Life in England, Scotland and Ireland|Joseph Tatlow
I have erected above 100 steam-engines on this principle, but never met with one accident or complaint against them.
Life of Richard Trevithick, Volume II (of 2)|Francis Trevithick