A consequence of Dedekind's independence theorem

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I first remind Dedekind's independence theorem

Let $G$ be a group and $\sigma_1,\cdots,\sigma_n$ characters of $G$ to a field $L$ that are $2$ by $2$ different. Then $\{\sigma_1,\cdots,\sigma_n\}$ is a linearily independent set over $L$.

Where

A character $\sigma$ of $G$ to $L$ is a group morphism $\sigma$ from $G$ to the multiplicative group $L^*$.

and

A set of characters $\sigma_1,\cdots,\sigma_n$ of $G$ to $L$ is called linearilly independent if $$a_1\sigma_1 + \cdots a_n\sigma_n = 0$$
implies that $a_1 = \cdots = a_n = 0$

Apparently a consequence of this is the fact that distinct ring homomorphisms of a field $K$ into a field $F$ are linearily independent over $F$.

I don't get this.

Indeed, ring homomorphisms are not from $(K^*,\cdot)$ to $(F^*,\cdot)$ so we don't fit into the setting of Dedekind's theorem.