Library Eusebius of Caesarea Preparation for the Gospel
Book 12, Chapter 26
[PLATO] [76] 'IF therefore there has either been in the boundless ages of the past, or is even now in some barbarous region lying far away out of our sight, or shall hereafter be a necessity for men eminent in philosophy to take charge of a State, I am ready to argue to the death in defence of this assertion, that the constitution which I have described has existed, and still exists, and will exist, whenever the Muse herself becomes mistress of the State: for it is not impossible that she should become mistress, nor are my descriptions impossible.'
English translation by E. H. Gifford, Eusebii Pamphili Evangelicae Praeparationis Libri XV (Oxford, 1903). Public domain. Digital text via Roger Pearse / tertullian.org.