It is well known that in Plato’s utopian ideal state there is no room for free artistic expression: artists are mistrusted and art works heavily censored. Less known is that, once they are properly selected and purified, art works are particularly valued by Plato. However, Plato completely disapproves of a certain category of art, which he defines as ‘mimetic’. ‘Mimetic art’ is a priori disqualified by him as morally bad, misleading and dangerous. It is therefore categorically forbidden in the ideal state. In practice, Plato identifies ‘mimetic art’ chiefly with Greek tragedy. We will go into a Jungian explanation of why this is the case. I hope to show that psychologically speaking Plato’s ideal state is an unstable construction. It is built on the repression of unconscious powers that may erupt any time. Tragedy is threatening to this construction because it undermines the unrealistic Platonic conception of man as an autonomous, rational being.