charge q such that $m\leq gqM_{\text{p}}$ in the theory. Arguments based on extremal charged back-holes and string theory examples give solid support to this conjecture, which has been generalized to multiple $U(1)$’s as well as antisymmetric tensor couplings in supergravity and string theory, see ref.[@WGC1; @WGC2; @WGC3; @timo] for some recent reverences and [@review; @vafafederico] for an introduction.

There are however two options concerning what is the most important physical principle underlying the WGC, either 1) It is something primarily related to black-holes and their stability or rather 2) It is the general principle of gravity being the weakest force which is the crucial point. If the second is true, the consequences would be paramount, since there are many physical instances in which interactions may potentially be weaker than gravity without black-holes playing (at least apparently) any role. In the present paper we want to argue that insisting in gravity being always and in any circumstance the weakest force, may have very important implications if applied to scalar particles.

In this paper we put forward the proposal of a [*Strong Scalar WGC*]{} which is defined by eq.(\[ours\]), corresponding to the statement that the self-interactions of a scalar must be stronger 