Sometimes, a sign has a name.
There is a minus sign in the Maxwell-Faraday equation:
∇ x E = - ∂B/∂t
That minus sign has a name, which is Lenz's Law.
Heinrich Lenz (1804-1865) wrote in 1833 that "An induced current is always in such a direction as to oppose the motion or change causing it."
The sign might be negative, but I look upon the Law as being positive. That is, in my opinion, Lenz's Law is a Good Thing. Because, otherwise, the electromagnetic universe would be profoundly unstable, with any perturbation resulting in positive feedback, amplification, and, ultimately, explosion!