The aim of this article is to draw attention to the breadth and importance of Mumford's philosophical outlook by exploring his critical appropriation of the theories of Marx and Jung which he employed to create a penetrating, visionary collection of works that offer us a powerful and timely insight into the ills besetting our current technological civilization. Mumford partially accepted Marx's matter–psyche dynamic but expanded it to include architecture, technology and urban planning. He surpassed the one-way process of Marxist historical-economic (...) teleology to form a conception of historical process based upon a dialectic interaction between mind and material conditions. He constructed a Jungian model of mind and explored its formative effect on material conditions. At the same time he criticized Jung's failure to engage with the external world, namely with those material conditions in urgent need of transformation. Like Jung he was concerned by the exclusion of religion from the modern scientific idolum, the dominant ideological presence, yet unlike Jung he extended his analysis further, considering not only the effect of religion on the individual but also its effect on the community. His theory of the dialectic interaction of material conditions and psyche is partly drawn from these two thinkers but transcends both by refusing to commit wholly to either. His incorporation, modification and rejection of elements of both Marx and Jung contributed more significantly than has so far been noted to his own critique of the present civilization and vision for the future. This vision involved a deeper awareness of the human personality, liberation from automatism and increased sensitivity to others and the natural world. This, according to the Mumfordian project, would be inexorably followed by a gradual withdrawal from the consumerism of the current technological civilization, the construction of a more personal and organic ideology and the subsequent regeneration of material conditions to nurture human nature. I therefore argue that it is essential to our understanding of Lewis Mumford that we witness his critical engagement with Marx and Jung and see the ways in which they inform and inspire this project. (shrink)