Before you begin a thing remind yourself that difficulties and delays quite impossible to foresee are ahead. ... You can only see one thing clearly, and that is your goal. Form a mental vision of that and cling to it through thick and thin.
If we have not achieved our early dreams, we must either find new ones or see what we can salvage from the old. If we have accomplished what we set out to do in our youth, we need not weep like Alexander the Great that we have no more worlds to conquer.