You've heard the story of the little train who was going up the hill with a heavy load, he wasn't sure he was going to make it so he told himself: "I think I can, I think I can, I think I can, I think I can." Until he got all the way to top.
This is almost the same for reality as well. Thinking that we can and telling ourselves we can accomplish anything leads us to believe that we actually can. Striving us to conquer even things we thought we weren't capable of. With that being said, anything and everything is possible if you simply believe it it possible.
"But how?" The answer is long and complicated and is still only described in theories. But here's what I think.
The Conscious mind is the part that takes all the information you hear and see when you're conscious (awake) like riding a skateboard or the Pythagorean Theorem. This part of the mind speaks out loud to where you hear your thoughts and pretty much has its own two parts based off of the things you want and the things you need. (What some people call the left and right brain).
The Unconscious mind takes all the information when you are unconscious (asleep) like dreams at night. This is the part of the brain that imagines or daydreams/dreams, which also includes the subconscious mind, but i'll get into that later.
The Subconscious mind is the part of the brain that takes compliments and takes negativity and takes everyday basic knowledge as if you learned them by heart. (In truth, you can't learn things by heart. The heart has a different purpose than to take up knowledge XD.) That's the part of the brain that usually can't forget simple thing like your birth name. The Subconscious mind is capable of doing anything. It's the part where you can convince yourself things like "my boyfriend is my soulmate" and things like that.
When people tell you that "Oh you look good today" and you smile, that's your subconscious taking in the compliment and acting upon it by giving you the reaction of smiling. If instead of smiling, you think in your head, I don't agree with this person, I think I'm ugly, that's your subconscious believing you are ugly and thinking less of yourself. Usually your subconscious will only believe that if you confirm to yourself that you're ugly (which you are not ugly at all <3 beautiful writers) and by that i mean simply telling yourself you are ugly, you will believe it in your head.
That's why telling yourself "I think I can, I think I can, I think I can, I think I can," will lead you to believe you actually can, making yourself strive to complete what you might've thought you couldn't do.
I used to watch videos and read things about how the conscious and subconscious mind worked, but I forget about how interesting and how much I loved doing that until I read this.