The belief in an external world independent of the perceiving subject is the basis of all natural science. Since, however, sense perception only gives information of this external world or of "physical reality" indirectly, we can only grasp the latter by speculative means. It follows from this that our notions of physical reality can never be final. We must always be ready to change these notions - that is to say, the axiomatic basis of physics - in order to do justice to perceived facts in the most perfect way.
Since that deluge of newspaper articles I have been so flooded with questions, invitations, suggestions, that I keep dreaming I am roasting in Hell, and the mailman is the devil eternally yelling at me, showering me with more bundles of letters at my head because I have not answered the old ones.
All our thoughts and concepts are called up by sense-experiences and have a meaning only in reference to these sense-experiences. On the other hand, however, they are products of the spontaneous activity of our minds; they are thus in no wise logical consequences of the contents of these sense-experiences. If, therefore, we wish to grasp the essence of a complex of abstract notions we must for the one part investigate the mutual relationships between the concepts and the assertions made about them; for the other, we must investigate how they are related to the experiences.
I see only with deep regret that God punishes so many of His children for their numerous stupidities, for which only He Himself can be held responsible; in my opinion, only His nonexistence could excuse Him.
Personally, I experience the greatest degree of pleasure in having contact with works of art. They furnish me with happy feelings of an intensity that I cannot derive from other sources.
One must console oneself with the thought that time has a sieve through which most of these important things run into the ocean of oblivion and what remains after this selection is often still trite and bad.
To act intelligently in human affairs is only possible if an attempt is made to understand the thoughts, motives, and apprehension of one's opponent so fully that one can see the world through their eyes.
A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port, together with some of the surrounding territory.
What I'm really interested in is whether God could have made the world in a different way; that is, whether the necessity of logical simplicity leaves any freedom at all.
A country cannot simultaneously prepare and prevent war. I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones. The distinctions separating the social classes are false; in the last analysis they rest on force.
Each ray of light moves in the coordinate system 'at rest' with the definite, constant velocity V independent of whether this ray of light is emitted by a body at rest or a body in motion.