Philosophical Problems of Quantum Physics

ΔpΔq = h / 2Π
Werner Heisenberg, Wandlungen in den Grundlagen der Naturwissenschaft, 1947 (lectures delivered and published separately between 1932 and 1948)
Ox Box Press, 1979
Translated by F.C. Hayes
Originally (1952) published by Pantheon Books as Philosophical Problems of Nuclear Science

1 Recent Changes in the Foundation of Exact Science

We call events 'past' if we can, at least in principle, find out about them trough some observation. We call them 'future' if we can still, at least in principle, intervene in their course. It corresponds with our daily experience to believe that events capable of observation are separated from those still open to change by an infinitely short instant which we call 'present'. This tacit assumption of physics has been proven wrong [...]

5 The Teachings of Goethe and Newton on Color in the Light of Modern Physics

Through Maxwell's discovery, light was recognized as an electromagnetic phenomenon. This led in turn to the recognition that electric and magnetic effects, light, invisible ultra violet and infra red rays and heat radiation are but different aspects of the same physical effect in spite of the fact that they belong to entirely different parts of our world of the senses.

p 72

The atom was progressively divested of all its 'sense-properties'. The only properties which appeared for a long time to be retained were geometrical ones —the atom took up space and position, and had a definite movement. The development of modern atomic physics, however, has removed even these properties by showing that the degree to which such geometrical concepts can be applied to the smallest particles depends directly on the experiment in which they are involved.

p 74

Goethe said that what the physicist observes with his apparatus is no longer nature.

6. On the Unity of the Scientific Outlook on Nature

[Isaac Newton :] ‘I don't know what I may seem to the world. But as to myself I seem to have been only like a boy playing on the seashore and diverting myself in now and then finding a smoother pebble or prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.’

We cannot assume such simple proportions as: biology relates to chemistry, as chemistry to physics. It would probably be more correct to say that a completely new level of perception and understanding has to be achieved.

7. Fundamental Problems of Present-day Atomic Physics

• Thales of Miletus: water is the origin of all things.
• Anaximander (of Miletus): fundamental polarity, the contrast between Being and Becoming.
• Heraclitus: Becoming assumed prime importance; fire became the basic element; war was the father of all things.
• Anaxagoras: several elementary substances, homogeneous and indestructible.
• Empedocles: earth, water, air and fire the 'basic roots'.
• Leucippus and Democritus of Abdera: transition to materialism. Full and Empty.
• Plato (Timaeus): 5 elements a single entity which happened to appear in different shapes (cube, tetrahedron, octahedron, [dodecahedron,] icosahedron — p 57).