Force needs to be solicited, prompted to express itself – the reflection into itself of the expressions that produces the unity of Force needs it as well. They are after all the same movement seen from two sides.
The ‘other’ of Force that solicits it, is also Force. What does that mean? I take it to mean something like this: when we understand two things in their relationship, each of them actively posits the other or is the invitation for the other to be active. In my former post I referred to Kant’s categories. Can we draw on that here?
Take substance and accident. Substance seems to denote the active principle, because it is expressing itself in its accidents. But the accidents, aren’t they ‘inviting’ the substance to this expression? After all, according to the concept of Force, the ‘substance’ of it is just the reflection into itself of the expressions. We can further say that a cause is ‘expressed’ in its effects. But can’t we also say that a cause is the reflection into itself of what we take as ‘effects’? In that sense the effects solicit the cause. The truth of these two forms of the category is then in the reciprocity, the third set of Kant’s relational categories. Just as in his Logic, the reciprocity is the thought form that expresses the inner truth of every idea of relation.
The language that Hegel uses indicates that he is thinking of two separate objects that invite each other to be active. There are two Forces present and each is independent and yet in a relation. Their relation is analyzed as follows:
The second Force solicits the first one and is itself a medium of expressions. The Force that is being solicited therefore appears as the One. However, the second Force that is doing the soliciting, is a medium of expressions only because it is itself solicited to be such. As being solicited it too, is a One.
Can we apply that to an example like this? Take a metal object and a magnet. The magnet and the metal object are equally independent things. Now the magnet is being effective because the metal object invites it to do something. It becomes this one magnet by the movement of the metal object. The magnet is solicited to be this One magnet. In that sense the metal object is a Force as well, because it certainly does something. Or rather in Hegel’s language: it expresses itself in its other. Therefore it can be seen as the One too, and the magnet that was first seen as soliciting, can be seen as the medium of expressions – the attraction it exercises being one of them.
That seems to be the meaning of Hegel’s statement:
Consequently, this distinction, too, which obtained between the two Forces, one of which was supposed to be the soliciting, the other the solicited, Force is transformed into the same reciprocal (!) interchange of determinateness. (p. 84)