Karl Barth explains this quite well in vol. III.2 of his Church Dogmatics (pages 399-409). His terminology is somewhat different. Instead of sense-certainty and the universal, Barth speaks of awareness and thinking. He writes:

 

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Perception always takes place in a compound act of awareness [sense-certainty] and thought [the universal].

 

It is not a pure act of thought, for in a pure act of thought we should not surmount the limits of self-consciousness and so we should be unable to receive and accept an other as such into our self-consciousness.

 

Neither is it a pure act of awareness [sense-certainty], for when I am merely aware of something and do not think it, it remains external to me and is not received into my self-consciousness.

 

Only the concept of perception can be divided in this way. And it is only for an understanding of the concept that we can allow the division. But perception is itself an undivided act, in which awareness makes thinking possible and thinking makes awareness possible.

 

Superficially we can recognize the two moments of human nature, body and soul, in the division of the idea of perception into awareness and thought.

 

It is natural and in a certain sense justifiable to say that awareness belongs to the body, i.e., its sense organs, and thought to the soul, so that the act of perception, which is single, has to be understood as an act of the whole man in the sense that one had to understand body and soul in him to be in a kind of distributed cooperation.

 

But the situation is more complicated than this. I am not only my soul; I am my soul only as I am also my body. I am not only my body; I am my body only as I am also my soul. Hence it is certainly not only my body but my soul which has awareness, and it is certainly not only my soul but also my body which thinks.

 

The two functions of perception cannot be distributed as though one were of the soul and the other of the body. But it can be affirmed that a special relation to the body is proper to the one, and a special relation to the soul to the other.

 

A special relation to the body can be ascribed to the act of awareness to the extent that it is in fact the outer and not the inner side of perception.

 

The soul has awareness, but this is possible only in so far as it has in the body its outer form and is thus open to the other of which it is aware. Body is the openness of soul. Body is the capacity in man in virtue of which an other can come to him and be for him.

 

So, too, a special relation to the soul can be ascribed to thinking inasmuch as it is in fact the inner and not the outer side of perception.

 

The soul can think only in so far as it is the inner form of the outer, the place in which the other can be received for which it is now open, thanks to the body.

 

[Barth repeats this argument in regard to activity in its two moments of desiring and willing. Here the argument is, perhaps, more evident. And Barth follows Hegel's view of the matter in opposition to that of Kant. He continues:]

 

In the concept of activity, as in that of perception, we have to do with two different functions. Desiring and willing characterize man as the distinct subject that he is.

 

Man's activity takes place in a single act of desiring and willing.

 

It does not take place [contra Kant] in a pure act of will. Pure volition would take place to some extent in a vacuum, since as such it would have no object, and no other in relation to which to exercise itself. What was purely willed would necessarily be purely internal. Pure volition is in fact a movement incapable of execution and can have nothing to do with activity.

 

Nor is it fulfilled in a pure act of desire. Pure desire would certainly have an object. But it would not as such be our movement in relation to the other.

 

So again we can quite well divide the concept--but only the concept--of activity into the ideas of desiring and willing. But activity is itself the undivided act in which desire makes the willing possible and the willing makes the desiring actual, the possibility and actuality being the free movement of a man in relation to an other.

 

There is indeed a special relation of desiring to the bodily nature of man, and of willing to the soul. But there is no partition. On the contrary, we have to understand both desiring and willing as both soulful and bodily, both being primarily of the soul and secondarily of the body.

 

Where I have no desire, I cannot will. But I do not by any means will everything which I desire; nor again do I not will everything for which I have no liking. When I will, I make up my mind.

 

The body itself does not decide or determine, though it offers to me the material for my desiring in the form of an urge.

 

It is I who decide and determine in relation to my desiring, not without parallel physical phenomena and conditions, but in such a way that I elevate myself above myself, above my physico-psychical desiring and therefore above my body, so that I am my own master and the master of my body.

 

When I will I abandon my neutrality towards myself and my desiring and take a position over against them both. But this abandonment of neutrality and occupation of position is as such my act, the act of my soul, in just the same way as must be said of thinking in relation to awareness.