Girls are evil?

Girls consume time and money    Girls=time*money
Time is money                Time=money
substitution principal        Girls=money*money=money^2
money is the root of all evil    money=sqrt(evil)
substitution principal        Girls=sqrt(evil)^2=evil
  Girls=Evil;  Q.E.D.

1 = (1)^(.5) = (-1^2)^(.5) = (-1)^(2*.5) = (-1)^1 = -1