Let $\mathbb{R}$ be the set of real numbers and the mapping $f : \mathbb{R} \to \mathbb{R}$ and $g : \mathbb{R} \to \mathbb{R}$ be defined by $f(x) = 5 - x^2$ and $g(x) = 3x - 4$, then the value of $(f \circ g)(-1)$ is