### Clue: Extremely foolish for London's earliest university to have Brown back in charge (7)
### Answer: LUNATIC 
 ### Explanation: Definition: Extremely foolish
 **The 1st letter of**(…'s earliest) "London" + U(abbrev. for "university") **plus**(to have) **reversal of**(… back) TAN(a brown colour) + IC(abbrev. for "in charge").