Positive liberty vs. Negative liberty
Positive liberty is a proactive process, springing from the need of individuals to feel as if they are in control of their decisions. One of the effects of posivite liberty is that people may feel they are more in control than they really are.
Negative liberty is the absence of meddling in one's individual decisions : "by being free in this sense I mean not being interfered with by others". Interesting side note: ideal Romantic artist is the embodiment of heroic individual negative liberty.
(from Isaiah Berlin, Four Essays on Liberty , 1969)
"In 1920 Stefan Wolpe, a 18 year old student at the Berlin Hochschule fuer Musik, ogranized a performance of Beethhoven's Fifth Symphony using eight phonographs on a stage each playing the Symphony simultaneously but at a different speed.
Many years later he repeated the performance using two phonographs and spoke of "one of the early Dada obsessions, or interests, namely, the concept of unforeseeability":