“A philosophy has a practical power: it contributes to the changing of the world.”
[O] : Introduction, 0.7
Semiotics and the Philosophy of Language (1984)
Context: A philosophy has a practical power: it contributes to the changing of the world. This practical power has nothing to do with the engineering power that in the discussion above I attributed to sciences, including specific semiotics. A science can study either an animal species or the logic of road signals, without necessarily determining their transformation. There is a certain 'distance' between the descriptive stage and the decision, let us say, to improve a species through genetic engineering or to improve a signaling system by reducing or increasing the number of its pertinent elements.
On the contrary, it was the philosophical position of the modern notion of thinking subject that led Western culture to think and to behave in terms of subjectivity. It was the position of notions such as class struggle and revolution that led people to behave in terms of class, and not only to make revolutions but also to decide, on the grounds of this philosophical concept, which social turmoils or riots of the past were or were not a revolution. Since a philosophy has this practical power, it cannot have a predictive power. It cannot predict what would happen if the world were as it described it. Its power is not the direct result of an act of engineering performed on the basis of a more or less neutral description of independent data.
Help us to complete the source, original and additional information
Umberto Eco 120
Italian semiotician, essayist, philosopher, literary critic… 1932–2016Related quotes

“Remember, each one of us has the power to change the world.”
9 October 2009.
Twitter messages
Context: Remember, each one of us has the power to change the world.
Power works in mysterious ways. You don’t have to do much. Visualise the domino effect And just start thinking PEACE.
The message will circulate faster than you think. It’s Time For Action. The Action is PEACE. Spread the word. Spread PEACE. I love you!

“Philosophy has been called the search for the Permanent amid the changing.”
The Usurpation Of Language (1910)
Context: Philosophy has been called the search for the Permanent amid the changing. With this account of philosophy there is no need to quarrel. But having accepted it, a distinction remains to be observed, a distinction of capital importance, which we are in constant danger of forgetting. It is one thing to find the Permanent; it is another thing to find a form of words in which the Permanent shall stand permanently expressed. It is one thing to experience something fixed and changeless; it is another thing to fix this something by a changeless definition. The first may be possible, while the second remains impossible for ever.

“The fleshless diet contributes to health and to a suitable endurance of hard work in philosophy.”
1, 2, 1
On Abstinence from Killing Animals

Source: 1910s, Mysticism and Logic and Other Essays http://archive.org/stream/mysticism00russuoft/mysticism00russuoft_djvu.txt (1918), Ch. 1: Mysticism and Logic

On Practice (1937)