Schweitzer begins by declaring that civilization is essentially ethical. As I understand him the essence of ethics is how we think about and treat one another and all manifestations of life. 

SPECIAL NOTE: The phrase "world and life view" is used to translate a German word that is also translated here as a "theory of the universe".   

"Entering on the question as to what is the real essential nature of civilization, I come to the pronouncement that this is ultimately ethical. I know that in thus stating the problem as a moral one I shall surprise and even disgust the spirit of our times, which is accustomed to move amidst aesthetic, historical, and material considerations…"  "I have come to the conviction that… the essence of civilization … depends on the mental disposition of the individuals and nations who exist in the world.  All other things are merely accompanying circumstances of civilization, which have nothing to do with its real essence."

"Creative artistic, intellectual, and material attainments can only show their full and true effects when the continued existence and development of civilization have been secured by founding civilization itself on a mental disposition which is truly ethical.   It is only in his struggle to become ethical that man comes to possess real value as a personality; it is only under the influence of ethical convictions that the various relations of human society are formed in such a way that individuals and peoples can develop in an ideal manner.    If the ethical foundation is lacking, then civilization collapses, even when in other directions creative and intellectual forces of the strongest nature are at work."

"The second point which I desire to obtain currency is that of the connection between civilization and our theory of the universe…."   Our loss of real civilization is due to our lack of a theory of the universe."

"Only as we succeed in attaining a strong and worthy theory of the universe, and find in it strong and worthy convictions, shall we again become capable of producing a new civilization…"

"Civilization, put quite simply, consists in our giving ourselves, as human beings, to the effort to attain the perfection of the human race and the actualization of progress of every sort in the circumstances of humanity and of the objective world…. "Firstly, we must be prepared to act affirmatively toward the world and life; secondly, we must become ethical."

"Only when we are able to attribute a real meaning to the world and to life shall we be able also to give ourselves to such action as will produce results of real value.   As long as we look on our existence in the world as meaningless, there is no point whatever in desiring to affect anything in the world.  We become workers for that universal spiritual and material progress which we call civilization only in so far as we affirm that the world and life possess some sort of meaning. "  "...It is impossible to convince men of the truth of world and life affirmation, and of the real value of ethics by mere declamation… "These beliefs must originate in man himself as the result of an inner ethical relationship to the world."   "…World and life affirmation must be the products of thought about the world and life.  Only as the majority of individuals attain to this result of thought and continue under its influence will a true and enduring civilization make progress in the world."

"The basic ethical character of civilization is the connection between civilization and our theories of the universe.   The question with which I conclude is this.   Is it at all possible to find a real and permanent foundation in thought for a theory of the universe, which shall be both ethical and affirmative of the world and of life?  The future of civilization depends on our overcoming the meaninglessness and hopelessness which characterize the thoughts and convictions of men today…  We shall be capable of this however only when the majority of individuals discover for themselves both an ethic, and a profound steadfast attitude of world and life affirmation, and a theory of the universe that's convincing and based on reflection." 

"A root idea of my theory of the universe is that my relationship to my own being, and to the objective world, is determined by reference for life… The theory of the Universe characterized by 'reverence for life" is arrived at by self-consistent thought, when persisted in to its ultimate conclusion…  Man finds a meaning for his life in that he strives to accomplish a spiritual and ethical self fulfillment and simultaneously, and in the same act, helps forward all processes of spiritual and material progress which have to be actualized in the world."

"I do not know how many or how few will allow themselves to be persuaded to travel with me on the road above.   What I desire above all things and this is the crux of the whole affaire is that we should all recognize fully that our present entire lack of any theory of the universe is the ultimate source of all the catastrophes and misery of our time and that we should work together for a theory of the universe and life in order that thus that we may arrive at a mental disposition which shall make us really and truly civilized men."