If I weren't reasonably placid, I don't think I could cope with this sort of life. To be a diva, you've got to be absolutely like a horse.
— Joan Sutherland

Ignorance is the first requisite of the historian -- ignorance, which simplifies and clarifies, which selects and omits, with a placid perfection unattainable by the highest art.
Lytton Strachey placidly quote

The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents. We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the deadly light into the peace and safety of a new dark age.
— H. P. Lovecraft

How lovely the little river is, with its dark changing wavelets! It seems to me like a living companion while I wander along the bank, and listen to its low, placid voice...
— George Eliot

People who are born even-tempered, placid and untroubled -- secure from violent passions or temptations to evil -- those who have never needed to struggle all night with the Angel to emerge lame but victorious at dawn, never become great saints.
— placidly quotation by Eva Le Gallienne