[Ten rozdział nie został jeszcze przetłumaczony.]
Let's have a closer look at it. Zoom into your document to be able and see the text frame of the first page completely or the upper half of it. (Please understand that we use rather small snapshots in this manual for several reasons.)
Here you can recognize well that each new paragraph starts with an indent now, this indent being a particularly beautiful indent, which is as wide as the text lines are high, 11 pt here. In general, a paragraph indent makes sense only with a new paragraph, delimiting it from the previous paragraph. Centuries ago publishers used to paint a paragraph symbol in the gap where we see the indent today, sometimes in red color. Someone must have been hard-up for time or money then and left out the paragraph symbol. Having the guts to keep this gap paid off. They found that an indent of a square size is enough to delimit one paragraph from the previous one in an optical proper manner. The square arises from the line height.
After this little historical digression it's obvious that at least the very first paragraph does not require an indentation.
Mark the first paragraph of your text with the mouse and click on
Body text, no indent
in the Text Ruler inspector afterwards.
The first paragraph will be reformatted without indent immediately.
And you have discovered now how to assign a new text ruler to any
paragraph of your text. Mark the paragraph, click the text ruler,
done.