Go for it now. The future is promised to no one.
If you think you can do it, you can.
Problems are not stop signs, they are guidelines.
Who seeks shall find.
I can, therefore I am.
Only the educated are free.
It's always too early to quit.
Always desire to learn something useful.
Things do not happen. Things are made to happen.
Begin to be now what you will be hereafter.
All the mathematical sciences are founded on relations between physical laws and laws of numbers, so that the aim of exact science is to reduce the problems of nature to the determination of quantities by operations with numbers.