It's always too early to quit.
Problems are not stop signs, they are guidelines.
Never complain and never explain.
Wherever you are - be all there.
Expect problems and eat them for breakfast.
Do not weep do not wax indignant. Understand.
The most effective way to do it, is to do it.
The wise does at once what the fool does at last.
Go for it now. The future is promised to no one.
If you think you can do it, you can.
I am a teacher, and I am proud of it. At Cornell University I have taught primarily undergraduates, and indeed almost every year since 1966 have taught first-year general chemistry.