Galileo Galilei

Galileo Galilei

Born: 1564. Died: 1642.


- Observation bears out the truth of the Copernican theory that the earth is not the center of the universe.

- Aristotle's claim that heavier bodies fall faster thab lighter ones can be disproved by observation.

- Controlled experimentation and the use of quantitative methods of reporting observations yield better results than do casual observations and extended discussion of qualities and tendencies.

- Authoritarian pronouncements about real phenomena must be tested against the evidence given us in nature.

- The universe is written in the language if mathematics.


Italian astronomer, mathematician, and physicist.

By his persistent investigation of natural laws he laid foundations for modern experimental science, and by the construction of astronomical telescopes he greatly enlarged humanity's vision and conception of the universe.

He gave a mathematical formulation to many physical laws.

Major Works of Galileo Galilei

- Dialogo dei due massimi sistemi del mondo (Dialogue Concerning the Two Chief World Systems), 1632
- Discorso del flusso e reflusso del mare (Discourse on the Tides), 1616
- Discorso Delle Comete (Discourse on the Comets), 1619
- Discorsi e Dimostrazioni Matematiche, intorno a due nuove scienze (Discourses on Two New Sciences), 1638
- Il Saggiatore (The Assayer), 1623
- Letters on Sunspots, 1613
- Letter to the Grand Duchess Christina, 1615 (published in 1636)
- The Little Balance, 1586
- Mechanics, c1600
- On Motion, 1590
- Sidereus Nuncius (The Sidereal Messenger), 1610

Quotes from Galileo Galilei

- "I think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments and demonstrations." (from "The Authority of Scripture in Philosophical Controversies")


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