If you're going through hell, keep going.
Never complain and never explain.
If you think you can do it, you can.
Without hard work, nothing grows but weeds.
It's always too early to quit.
To know oneself, one should assert oneself.
Be kind whenever possible. It is always possible.
Leap, and the net will appear.
Only the educated are free.
By failing to prepare, you are preparing to fail.
Many who have had an opportunity of knowing any more about mathematics confuse it with arithmetic, and consider it an arid science. In reality, however, it is a science which requires a great amount of imagination.