The figure below is roughly that from page 1045 of Russell and Norvig's Artificial Intelligence: A Modern Approach, 3rd edition. It is a simple description of what it is to be human. (Of course it's oversimplified, it takes up less than a page!) We look at the world with our senses and observe what it is like. We have some idea of how the world evolves, what actions we can perform, and what our actions do. We use a value system to decide what is best to do at any given moment.
We are all scientists. To be an intelligent creature is to be a scientist. As professional scientists we just work harder at it. Scientism is in our inherent nature.