What is freedom?

What is Freedom? Does freedom exist?

Freedom according to Teilhard de Chardin:
That life has a meaning, meaning that what we do has an effect.
That what we do has an impact on the Universe.
We are free to play a role (or not) in this meaningful life.

Freedom according to Lucado:
The freedom to choose right from wrong, to choose right for the right reasons

Freedom according to Marx?