An open-door policy doesn't do much for a closed mind.

An open-minded and diverse population that readily shares information, encourages experimentation, accepts failure and dispenses with formality and hierarchy is what makes Silicon Valley the successful hub that it is.

An open-minded person running a business might catch a problem faster than a closed-minded person. And when they identify a problem, they can fix it much faster.

An opening line should invite the reader to begin the story. It should say: Listen. Come in here. You want to know about this.

An opening statement is like a guide or a road map. It's a very delicate thing.

An opera begins long before the curtain goes up and ends long after it has come down. It starts in my imagination, it becomes my life, and it stays part of my life long after I've left the opera house.

An opera may be allowed to be extravagantly lavish in its decorations, as its only design is to gratify the senses and keep up an indolent attention in the audience.

An opera singer is like an athlete before a match. An athlete cannot overdo anything. In order to perform at the highest possible level, you need to refrain from activities so as to be able to express this power.

An operetta is simply a small and gay opera.

An opinion is not to be respected simply because somebody holds it. More or less any obnoxious viewpoint one can think up is probably held by somebody somewhere. There are right-wing Afrikaners who believe that Nelson Mandela was evil.

An opinion which excites no opposition at all is not worth having!

An opinion, right or wrong, can never constitute a moral offense, nor be in itself a moral obligation. It may be mistaken; it may involve an absurdity, or a contradiction. It is a truth; or it is an error: it can never be a crime or a virtue.

An opportunity to honor the legacy of the lives drawn into the lines in my face, the broad of my nose, the dark of my eyes, the fullness of my lips, and coal in my complexion.

An opportunity to work is good luck for me. I put my soul into it. Each such opportunity opens the gates for the next one.

An opposition that won't oppose paralyses our political and democratic system.

An oppressed people are authorized whenever they can to rise and break their fetters.

An oppressed people will always rise.

An oppressive government is more to be feared than a tiger.

An oppressive nature is like inclement weather, surrounding others and crushing them down with its infectious gloom.