Problems are not stop signs, they are guidelines.
I can, therefore I am.
It's always too early to quit.
By failing to prepare, you are preparing to fail.
The dog that trots about finds a bone.
If you're going through hell, keep going.
Never complain and never explain.
Quality is not an act, it is a habit.
Begin to be now what you will be hereafter.
Expect problems and eat them for breakfast.
The grounding in natural sciences which I obtained in the course of my medical studies, including preliminary examinations in botany, zoology, physics, and chemistry, was to become decisive in determining the trend of my literary work.