A popular Bible verse has it that whatever the mind thinketh so is he.....
You are today the product of what you think, the mind has the ability to manipulate a man's action.
Whatever you think is what you become, if you think prosperity, you become prosperous, if you think failure you become a failure, you become a failure because you won't have the passion to make effort.
Mary key Ash started "if you think you can, you can and if you think you can't you are right.
Your chance of becoming an achiever in life depends on how you discipline your mind.
Think positive
That's a good one, especially the quote by Mary Key Ash.