Common sense is the collection of prejudices acquired by age eighteen. OK, so much for common sense. Mere thinking cannot give us a sense of the ultimate and fundamental ends. OK, so let's NOT think. The only real valuable thing is intuition.
Any intelligent fool can make things bigger, more complex, and more violent.
Everything should be made as simple as possible, but not simpler. We can't solve problems by using the same kind of thinking we used when we created them. It seems so clear when you put it that way. But it seems as obvious as putting two and two together. Do not worry about your difficulties in Mathematics.