We cannot command Nature except by obeying her.
To keep that absolute freedom we cannot be obliged to anyone.
We cannot direct the wind, but we can adjust the sails.
We cannot be a civilized society if these terrorists are going to have their ways.
We cannot comprehend what comprehends us.
When it comes to human dignity, we cannot make compromises.
When we cannot be delivered from ourselves, we delight in devouring ourselves.
We cannot despair of humanity, since we ourselves are human beings.
It is my view that we cannot conduct foreign policy at the extremes.
There are no problems we cannot solve together, and very few that we can solve by ourselves.
For all of its uncertainty, we cannot flee the future.
We cannot afford idleness, waste or inefficiency.
Knowledge is knowing that we cannot know.
We cannot allow religious hooligans to place limiting points on thought.
What we cannot deny is that there's an association between exclusion, segregation, non-violent extremist thinking, and jihadism.
We cannot always oblige; but we can always speak obligingly.
We cannot let Obamacare expand geographically by setting up state exchanges, nor can we extend Obamacare's unlawful subsidies.