In 1666, Isaac Newton drew attention to the iridescent color of stars in a telescope. Trying to explain this phenomenon, he conducted an experiment. Newton in his experiments used sunlight, which he passed through a narrow opening in a window shutter through a prism. The light disintegrated into all colors of the rainbow. So he discovered that white light consists of many colors mixed with each other.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.