They often changed their name before being called "complex". In his Algebra, in addition to the usual signs + and –, Bombelli introduced two new "operators", piu di meno and meno di meno, to avoid √–1 and –√–1.
To each his own neologisms! Albert Girard, for his part, in Invention nouvelle en algèbre (1629), coins the term "enveloped solutions" for the roots of the equation x4 = 4x + 3 — numbers with nothing real about them, which Cardano says are "more sophisticated than real". Others call them "inexplicable" or "impossible". Descartes named them "imaginary" in 1637, but Leibniz distrusted these "monsters of the world of ideas", which for him still had no reality.
