A long and unbroken chain of social and political activists, including M K Gandhi, B R Ambedkar, Paulo Freire, Martin Luther King, Desmond Tutu, Thich Nhat Hanh and bell hooks, centred their attempts at social transformation around a spiritual understanding of the world. They brought to bear reconstructed spiritual resources to address what they saw as the key challenges of their own time and context. Their work shows that without the inner transformation proposed by the ancient science of spirituality, it would prove impossible to build a society based on liberty, equality and fraternity. I would go further and argue that the insights we can draw from this science are critically essential for the very survival of humanity, indeed of all life on earth, in this era of the Anthropocene.