Luciano Floridi

To be precise about what we mean by physical, and everything has to be physical because even GitHub, you know, has to store data.

its data in some sort of hard drive or magnetic field or whatever technology, but it's not storing it in nothingness.

So knowledge, information always has this form of physical embodiment.

Now, I think we tend to think about it as non-physical because it is a thing that is not a thing, which is the same as temperature.

You wake up, you look at your phone and you see the temperature and you decide how you're going to dress and nobody has any doubt that temperature is something that can be measured.

But it took about like 2000 years for us, you know, as a species to figure out, you know, what temperature was and the fact that it could be measured.

And there were two fundamental difficulties that I would say made it difficult for us to understand, you know, temperature.

The first one is that first people thought that hot and cold were two separate things.

OK, so that temperature was like a mixture of the two.

It's like when you make green out of blue and yellow.

OK, and it took a while for people to understand that cold was the absence of heat and not that cold and heat were two different quantities that were tempered together.

They were mixed.

So temperature actually means mixture, not, you know, like what we now mean by temperature.

The other thing that was very difficult to understand is that people thought that temperature was a thing, was some sort of fluid that grabbed onto things.

So let's say if you had a steel rod that is hot, is that steel rod kind of like has this sort of invisible fluid that is heat.

And they had good reasons to believe that it was an invisible fluid because it could flow.

Let's say you could connect that rod to something that was cold and that cold thing was going to warm up because that fluid was going to be flowing in that direction and so forth.

So they thought that it had a physicality as a thing.

A brilliant Englishman, Jowell, basically figures out that that is not the case, that temperature is not a thing.

And the way that they do it is through this observation, which I don't know if you know how cannons used to be built.