What does "say "i can" or say" i can't", and you're right either way." mean? ?

Your words determine what will happen. If you're a positive person and say "I can do it," then you'll be able to do it, if you keep telling yourself this over and over again. If you're a negative person and say "I will never be able to do it, I can't," then you won't be able to. Try this out on yourself! Grab a ball of clay and tell yourself "I can make something good out of this," you'll see a beautiful piece of artwork right there in your hands when you're finished. If you grab that clay and tell yourself "I can't do it, it's going to look terrible," then it will. I've tried it before for a school art project and I told myself I didn't know how to do it and I couldn't, and it didn't come out the way I wanted to. See how your words affect how you do things? You're right either way!! :)