For those guys who are always worried or concerned about the future and feel depressed about the past, I highly recommended you to read the Chapter 2 of the book How to Stop Worrying and Start Living. There are some quotes I marked down from Dale Carnegie's book that I wanna to share with you.

'I want you to think of your life as an hourglass. You know there are thoudsands of grains of sand in the top of the hourglass; and they all pass slowly and evenly through the narrow neck in the middle. Nothing you or I could do would make more than one grain of sand pass through this narrow neck without impairing the hourglass. You and I and everyone else are like the hourglass.

When we start in the morning, there are hundreds of tasks which we feel that we must accomplish that day, but if we do not take them one at a time and let them pass through the day slowly and evenly, as do the grains of sand passing through the narrow neck of the hourglass, then we are bound to break our own physical or mental structure.'

'One grain of sand at a time. One task at a time. Have no anxiety about the morrow.'

'The best possible way you can prepare for tomorrow is to concentrate with all your intelligence, all your enthusiasm, on doing today's work superbly today.'

'During the Second War War, our military leaders planned for the morrow, but they could not afford to have any anxiety."I have supplied the best men with the best equipment we have," said Admiral Ernest J. King, who directed the United States Navy, "and have given them what seems to be the wisest mission That is all I can do. "If a ship has been sunk," Admiral King went on, " I can't bring it up. If it is going to be sunk, I can't stop it. I can use my time much better working on tomorrow's problem than by fretting about yesterday's. Besides, If I let those things get me, I would not last long."

The chief difference between good thinking and bad thinnking is this: good thinking deals with causes and effects and leads to logical constructive planning; bad thinking frequently leads to tension and nervous breakdowns.

Keep thou your feet: I do not ask to see the distant scene; one step enough for me.