If you think you can do it, you can.
The secret of getting ahead is getting started.
If you can dream it, you can do it.
You never know what motivates you.
After a storm comes a calm.
Expect problems and eat them for breakfast.
Be gentle to all and stern with yourself.
Either you run the day or the day runs you.
Well done is better than well said.
The wise does at once what the fool does at last.
In hard-core science fiction in which characters are responding to a change in environment, caused by nature or the universe or technology, what readers want to see is how people cope, and so the character are present to cope, or fail to cope.