The Fourth Dimension
GA 324a
Questions and Answers VI
1 October 1911, Basel
QUESTION: What is electricity?
Electricity [Note 20] is light in the sub-material state, light compressed to the greatest possible extent. We must also attribute inwardness to light,—light is itself at every point. Warmth can expand into space in three directions, but in the case of light we must speak of a fourth direction. It expands in four directions, with inwardness as the fourth.
Notes of a question-and-answer session after the lecture to members entitled "Die Ätherisation des Blutes. Das Eingreifen des ätherischen Christus in die Erdenentwickelung" in Das esoterische Christentum und die geistige Führung der Menschheit (GA 130).