The world is an interesting place full of interesting things to learn, discover, think about, and create! Because of this, there is no single way to measure how smart a person is and it would be impossible to say who is or was the very smartest person in the world!
For example, many people might say that Albert Einstein was the smartest person to ever live because of the amazing scientific discoveries he made. Others might consider William Shakespeare to be the smartest person in history because of all the great plays and poetry he wrote!
A person who is smart can be good at math and science, or good at painting and philosophy! – In terms of being smart, doing well in school is very important but there are also other important ways of looking at intelligence such as a person’s approach to looking at the world, asking questions, seeking knowledge, and discovering or creating new things in the process!