concrete idea

It would be impossible for any language to express every concrete idea by an independent word or radical element.

Thus it is only the truly concrete Idea that can generate the true shape, and this correspondence of the two is the Ideal.

The concrete idea of a closed fist or an open hand with outstretched fingers, is what is upper-most in his mind.

We must have a concrete idea of anything, even if it be an imaginary idea, before we can comprehend it.

He considers (it may be) the concrete idea of moral activity.