The phrase "Nature is based on experiment and observation" is not a commonly attributed quote to any specific person. It's a general principle that underpins the scientific method, which has been developed and refined over centuries by many individuals.

However, some key figures who emphasized the importance of observation and experimentation in understanding the natural world include:

* Francis Bacon (1561-1626): A philosopher who championed empirical methods and argued for inductive reasoning. He believed that knowledge should be based on observation and experimentation, not just on ancient texts or speculation.

* Galileo Galilei (1564-1642): An astronomer and physicist who made groundbreaking observations with his telescope and conducted experiments that challenged the prevailing Aristotelian view of the universe.

* Isaac Newton (1643-1727): A physicist and mathematician who developed the laws of motion and universal gravitation based on observation and experimentation.

* Charles Darwin (1809-1882): A biologist who proposed the theory of evolution by natural selection, which was based on extensive observation of nature and experimentation with artificial selection.

It's important to remember that the idea of using observation and experimentation to understand the natural world has been a long and evolving process, with contributions from many individuals throughout history.