scientific knowledge is not what we can verify directly, as positivists expected. On the contrary, it is based on theoretical constructs that can be contradicted by empirical observations. We hold valid a theory that offers predictions that are corroborated as long as it has never been contradicted (“falsified”) by reality.

all these are “theoretical entities” that cannot be perceived directly by the senses but are postulated by science to account for the complexity of phenomena in a coherent way.

The concepts of “stasis” and “motion” are much more complex than our everyday experience indicates. Similarly, with his theory of special relativity, Einstein understands that the idea of simultaneity—of “now”—is not absolute either, but instead relative to the observer’s state of motion.

Philosophy school textbooks tell us that the first philosophical school was the Ionic school, which consisted of Thales, Anaximander, and Anaximenes.

Considered in this light, the process delineated by Thales is nothing else than the process of scientific thinking.

The point is that we are always immersed in a given culture, and it is impossible to step outside.

Anaximander’s greatness lies in the fact that on the basis of so little, in order to better account for his observations, he redesigns the universe.

In the history of science, perhaps the only other example of a conceptual revolution comparable in greatness to Anaximander’s is the Copernican revolution, opened by the publication of Copernicus’s treatise in 1543.[*] Like Anaximander, Copernicus rethinks the map of the cosmos.

But in science it is not difficult to come up with ideas; it is difficult to come up with workable ideas, to find a way to compose and articulate new ideas as part of a whole that is consistent with the rest of our knowledge, and to convince others that the entire process is reasonable.