Fields & Energy

Fields & Energy

Home
Archive
Leaderboard
About

Share this post

Fiat Lux
Fiat Lux
A New Adaptation of Galileo's "Two New Sciences" for Modern Readers

A New Adaptation of Galileo's "Two New Sciences" for Modern Readers

John Plaice's avatar
John Plaice
Jan 07, 2024
6

Share this post

Fiat Lux
Fiat Lux
A New Adaptation of Galileo's "Two New Sciences" for Modern Readers
14
1
Share
Cross-post from Fiat Lux
Fields & Energy takes a high-level pass through the history of physics to help establish a few basic concepts you'll need to understand later on: concepts like the distinction between inductive and deductive thinking and the long history of the atomic/particle versus the plenum/wave models. If you're enjoying my excursion into this history, you ought to check out Substacks that focus on these areas in particular. One such is John Plaice's excellent Fiat Lux Substack. This post of his highlights the importance of reading the old masters (like Galileo) to understand their thinking. Modern adaptations that translate the original prose into modern mathematical physics parlance aid in the understanding. What's the potential downside? Answer in the comments! -
Hans G. Schantz

Galileo’s last work, Discorsi e Dimostrazioni Matematiche, intorno a due nuove scienze (Two New Sciences), published in 1638 while he was in house arrest, is his most important work. According to Alessandro De Angelis,1

Two New Sciences contains, to mention only some of its main discoveries, the principle of inertia, the description of the motion of falling bodies, the observation that bodies of different weight fall with the same acceleration in vacuo, a demonstration (correct only at the first order) of the isochronism of pendulum oscillations, a demonstration of the parabolic motion of projectiles, and innovative considerations related to acoustics and music. [p.xx]

Unfortunately, the most commonly available English-language translation, undertaken by Henry Crew and Alfonso da Salvio, published in 1914,2 is problematic. In one of my first posts, How Two English-language Translators of Galileo Permanently Changed His Words, I presented Alexandre Koyré’s find that this text includes an egregious mistranslation, confusing “I have discovered” with “I have discovered by experiment.”

Thanks for reading Fiat Lux! Subscribe for free to receive new posts and support my work.

So when I decided to study the Two New Sciences in more detail, I went looking for something better. It turns out that Stillman Drake, the English-language biographer of Galileo, published a translation of Two New Sciences in 1974.3 This is much easier to read.

But then I came across something completely different. Alessandro De Angelis, professor of physics at the University of Padua, where Galileo himself was professor for 18 years, recently published an English-language adaptation of the complete Two New Sciences, using modern algebraic notation.

The result is quite striking. Consider, for example, this theorem from Drake’s translation:

PROPOSITION I. THEOREM I

The time in which a certain space is traversed by a moveable in uniformly accelerated movement from rest is equal to the time in which the same space would be traversed by the same moveable carried in uniform motion whose degree of speed is one-half the maximum and final degree of speed of the previous, uniformly accelerated, motion. [Third Day, p.165]

In De Angelis’s version, this becomes: [Day Three, p.105]

For the modern reader, it is a lot easier to read De Angelis’s version. However, the structure of the two is very different, and Galileo’s thoughts are more easily followed reading Drake’s translation. So, in my opinion, a careful reading in English of the Two New Sciences should be undertaken by placing side-by-side Drake’s translation and De Angelis’s adaptation, and reading them simultaneously.


If you wish to donate to support my work, please use the Buy Me a Coffee app.

Buy Me a Coffee!

1

Alessandro De Angelis. Galileo Galilei’s “Two New Sciences” for Modern Readers. Springer, 2021.

2

Galileo Galilei. Dialogues Concerning Two New Sciences. Translated from the Italian and Latin into English by Henry Crew and Alfonso de Salvio. New York: MacMillan, 1914.

3

Galileo Galilei. Two New Sciences, Including Centers of Gravity & Force of Persuasion. Translated by Stillman Drake. University of Wisconsin Press, 1974.

6

Share this post

Fiat Lux
Fiat Lux
A New Adaptation of Galileo's "Two New Sciences" for Modern Readers
14
1
Share

No posts

© 2025 Hans G. Schantz c/o Substack
Privacy ∙ Terms ∙ Collection notice
Start writingGet the app
Substack is the home for great culture

Share