10 R. It is then plain to you that a line cannot possibly be longitudinally divided into two? A. Plainly so. R. What of a cross-section? A. This, of course, is possible to infinity. R. But is it equally apparent that if, beginning with the centre, you make any sections you please of a sphere, no two resulting circles will be equal? A. It is equally apparent. R. What are a line and a sphere? Do they seem to you to be identical, or somewhat different? A. Who does not see that they differ very much? R. If then you know this and that equally well, while yet, as you acknowledge, they differ widely from each other, there must be an indifferent knowledge of different things. A. Who ever disputed it? R. You, a little while ago.
For when I asked you what way of knowing God was in your desire, such that you could say, It is enough, you answered that you could not explain this, because you had no perception held in such a way as that in which you desired to perceive God, for that you knew nothing like God. What then? Are a line and sphere alike? A. Absurd. R. But I had asked, not what you knew such as God, but what you knew so as you desire to know God. For you know a line in such wise as you know a sphere, although the properties of a line are not those of a sphere. Wherefore answer whether it would suffice you to know God in such wise as you know that geometrical ball; that is, to be equally without doubt concerning God as concerning that.
Source: Soliloquies (New Advent)