Using rhetorical questions in speeches is a great way to keep the audience involved. Don't you think those kinds of questions would keep your attention?
Pay especial attention to speaking in public.

Private memo to himself (1868)
Prepare your heart and mind before you prepare your speech.

Thirty Methods of Influence (1991)
Speech after long silence; it is right,
All other lovers being estranged or dead ...
That we descant and yet again descant
Upon the supreme theme of Art and Song:
Bodily decrepitude is wisdom; young
We loved each other and were ignorant.

The Winding Stair and Other Poems, 1933, After Long Silence
The true use of speech is not so much to express our wants as to conceal them.

The Bee


On Anger: "For every minute you remain angry, you give up sixty seconds of peace of mind."
On Destiny: "Our destiny exercises its influence over us even when, as yet, we have not learned its nature: it is our future that lays down the law of our today."
Human, All Too Human
On Friendship: "A crowd is not company; and faces are but a gallery of pictures; and talk but a tinkling cymbal, where there is no love."