Literally: public – private – blend / confuse – equal
Alternately: Failing to properly differentiate between public and private business. Getting one’s private interests and personal affairs entangled in public policy-making. Using a public institution for private profit – in a word, corruption. (I’m sure you can think of a contemporary example!) Alternately, allowing one’s private life to interfere with school, work, or some other aspect of one’s place in society.