This is the last slide from last time. I'm not gonna go back over it. It's got these six questions, but we're shifting tonight away from Astronomy for five weeks. The 11th week of the course, we'll come back to Astronomy. And what's really important for you to have gotten out of the first five weeks on astronomy, what's really important is you understand these six questions.

But that requires a little bit of comment because to feel the erotetic logic is underdeveloped and it turns out that it probably isn't even perfectly logic. Collingwood is the one person to write significantly about questions and he's the one who introduced what's called, think he called, the give rise to relation.

If you want to understand the question you need to know what gave rise to it. And so, what I want here, is I want you for each of these questions, to understand what gave rise to it in the first place. Second, why it became so important by 1642.

And third, why it was resisting straightforward answer, any kind of resolution. If you understand that for these six questions, you've gotten everything you need to get out of the first five weeks of this course in terms of preparing for Newton. Because of course, Newton understood just where these questions came from.

Why they were proving difficult? Why they were important? And he addresses all of them, these six. He doesn't successfully address the one about distance, but all of the others he's quite preoccupied with. So, that's the point. You don't have to know everything about Astronomy. How much you choose to learn about Astronomy is up to you.

But I do want you to appreciate that these five questions we're really very much at the forefront by 1642. They don't go away over the next 42 years, as you'll see. If anything they get more complicated, all of them. Yeah, not one of them really goes away. All right, so for the next five weeks, we're gonna be doing mechanics, but that requires some explanation.

Technically the way I like to describe it is what we're gonna be doing is the mechanics of motion. And I have to distinguish that because the term mechanics was already very much in circulation going quite far back. But it was the mechanics of the balance, the lever, the screw, the pulley, the wedge, and starting with Leonardo Da Vinci, the inclined plane.

Where we think of it as statics but it's, they thought of it as machines. Machines to do things like lifting, making lifting easier, et cetera. And that science probably goes back before Archimedes but it gets quite rich with Archimedes. And the only name up there that really made major contributions to statics, beside Archimedes, is Stevin.

He was a little bit older, 20 years older, both born 16 years before Galileo died, 22 years before him. Steven in a series of volumes works out what we think of as statics to just an enormous level of perfection. And because he was Dutch, he had a huge influence on Huygens who will be the person we aiming to get to in our five weeks in mechanics cuz he ends up being the most important person.

I have no expectation that Galileo himself read Stevin. Stevin's in Latin, it's accessible, but almost certainly, Viviani who prepared the second edition, the posthumous edition of Two New Sciences, read him because of the diagram that I'll show later to try to justify what. Drake calls Galileo's postulate is a diagram right out of Stevin.

It's possible Viviani arrived at it separately, but perhaps not. The other Dutch name up there I threw up there is Beeckman. He's going to show up week after next. He's the person young Descartes worked with, and ended up getting some of the same results as Galileo got on motion independently of Galileo in the 1618, 1619 period, when Descartes was quite young.

He was 22 or 23 years old, and he linked up with Beeckman when he ended up getting out of the German army, I guess it was the German army. People may know his biography, but he was conscripted in working in the military and as he got out of that, he worked with Beeckman for a period and Beeckman was very much doing mechanics of motion.

The two medieval figures, well the two groups, Miltonians are a whole group at Oxford. And John Buridan, a fairly major philosopher, made famous precisely on his work of motion. They both locked at what we now call, what Galileo called, uniformly accelerated motion. I'll pass around, there is a classic work of translation of works and mechanics in the Middle Ages by Marshall Claget one of the principle founders of modern history of science.

My copy is you'll be able to tell partly from those book marks is Bernard Cowen's copy. I had the good fortune of inheriting whatever books I wanted from Bernard and this is a book I very much wanted. Oresme is particularly important here because there's no question Galileo, he definitely knew Oresme and Oresme's proof of whats called the Mean Speed Theorem.

Which Galileo offers himself and is essentially the same proof but we know Oresme] was being taught in Padua when Galileo was there. What he know of the Mertonians probably not much. And I don't know what he knew of Buridan. The four Italian names and I'll pass that book around as well because it's a collection of translations of the four of them.

They were working largely on mechanics of motion as a matter of fact. Though, Da Vinci was more concerned with incline plain, pushing things up incline plains and lowering them, but the point in the whole group is Galileo was not sitting there in isolation things were going on around him.

Though in his particular case, he does have claim to developing a new science because nobody of those before him, on motion, came close to developing it to the level he did that is calling it a science seems wildly premature for all of the rest of them. They were trying to get to where Galileo got, is probably a better description.

There's stuff among the Italian tradition on projectile motion, probably initiated by the military Galileo did early work for the military. Military has always been a nice source of funding if you want to do research, and so that was true for some of them.