“We have no longer an outside and an inside as two separate things. Now the outside may come inside and the inside may and does go outside. They are of each other. Form and function thus become one in design and execution if the nature of materials and method and purpose are all in unison.”

“How many understand that Nature is the essencial character of whatever is. It's something you'll find by looking not at, but in, always in. It's always inside the thing, and it makes the outside. And some day, when you get sufficiently proficient in understanding the use of the term, you can tell by the outside pretty much from what's inside.[...] But everything that's ever going to be of use to you in architecture or in life or anywhere you go or whatever you do is going to be Nature, in some of its immensely varied forms. So varied that there's no end to the variety imaginable."Nature" September 7, 1958”

“Every idea that is a true idea has a form, and is capable of many forms. The variety of forms of which it is capable determines the value of the idea. So by way of ideas, and your mastery of them in relation to what you are doing, will come your value as an architect to your society and future. That's where you go to school. You can't get it in a university, you can't get it here, you can't get it anywhere except as you love it, love the feeling of it, desire and pursue it. And it doesn't come when you are very young, I think. I believe it comes faster with each experience, and the next is very simple, or more simple, until it becomes quite natural to you to become master of the idea you would express."Idea and Essence" September 7, 1958”

“Now a work of art is a work of nature, but it is a work of human nature. It is a work of the mind: and it's a work of the mind in circumstances for an occasion which, to which, for which, and which it may be supremely natural and simple and effective."The Nature of Art" December 19, 1954”

“As we live and as we are, Simplicity - with a capital "S" - is difficult to comprehend nowadays. We are no longer truly simple. We no longer live in simple terms or places. Life is a more complex struggle now. It is now valiant to be simple: a courageous thing to even want to be simple. It is a spiritual thing to comprehend what simplicity means.”

“An idea is inevitably a coordination. It is a coming together of something that is separate or disorganized or incomplete. With an idea you begin to feel into the nature of that incompleteness."Nature and Idea" December 30, 1956”

“Philosophy is to the mind of the architect as eyesight to his steps. The Term 'genius' when applied to him simply means a man who understands what others only know about. A poet, artist or architect, necessarily 'understands' in this sense and is likely, if not careful, to have the term 'genius' applied to him; in which case he will no longer be thought human, trustworthy or companionable. Whatever may be his medium of expression he utters truth with manifest beauty of thought. If he is an architect, his building is natural. In him, philosophy and genius live by each other, but the combination is subject to popular suspicion and appellation 'genius' likely to settle him--so far as the public is concerned.”