Philosophy: When is a "lever" no longer a "lever"? - Page 7

#61: Post by **peacecup** » September 30th, 2023, 7:06 am

It is the piston that defines lever machines in my opinion as stated earlier. And it is the largely laminar flow created by the piston that defines lever espresso.

#62: Post by **donn** » September 30th, 2023, 9:58 am

I think we're lucky there's no need to define a boundary.

If there were, the nature of the boundary would depend on what it's needed for.

If we were governed by righteous curmudgeonry ... we all know very well what a lever machine is, and isn't.

If we were convinced that lever machines characteristically have a special brewing dynamic, and we were really interested in them for only that reason, we'd need a different boundary.

If we were survivalists or for whatever reason interested in machines without motors, yet another boundary. Etc.

#63: Post by **Jake_G** » September 30th, 2023, 10:19 am

peacecup wrote:It is the piston that defines lever machines in my opinion as stated earlier. And it is the largely laminar flow created by the piston that defines lever espresso.

Then why aren't they "piston" machines?

I don't disagree with you, but the Rossa machines use a hand crank or air pressure to move a piston. I agree that they "might be" lever machines, kinda like "you might be a redneck if...".

But what about the Duvall and Swiss Unica Pro, which both move a piston through a cylinder by means of a stepper motor. Same concept as the Rossa HC, but instead of hand crank, it is now computer-controlled stepper motor crank...

I think the piston is necessary but insufficient.

#64: Post by **jpender** » September 30th, 2023, 10:54 am

mathof wrote:Words are used to serve purposes. For example, H-B moderators have to decide which machines should be discussed in the Lever forum as opposed to the forum labelled Espresso Machines. This has to be a matter of judgement, as it is evident from this thread that it is not possible to agree necessary and sufficient conditions for inclusion in the relevant category.

But this is the normal state of things in most spheres of language. What we normally do is project from a small set of samples to new cases, as a child might do after seeing the word dog applied several times to a new animal they encounter. On being told that the new animal is in fact a cat, the child would not reflect on the relevant conditions for the application of the words dog and cat, but would simply learn by further examples what to say. The process is akin to training generative AI.

I agree with this well worded post.

There's a kind of club here, the LMDWP (I probably messed up the acronym) that I have never felt like I could join as I have a Cafelat Robot. Cafelat calls their product a lever machine but it doesn't really look like what I think of as a lever. To me it doesn't pass the "look" test. It passes other tests. In some ways a manual lever machine is more of a lever than a spring lever where the spring supplies the force to the piston instead of the lever. But the Italian spring lever is a quintessential lever machine so of course it's a lever. It looks exactly like one.

#65: Post by **drgary** » September 30th, 2023, 12:48 pm

And still most people here consider the Robot a lever. If something doesn't pass one test, since we can't have an exact definition, we can still have a general consensus.

Here's another boundary. Some early stovetop caffetieres had levers. Were they primarily espresso machines, atomics or moka pots? It depends.

And then there are lever machines that are poorly designed but are still levers, like the Enrico of Italy Italianstyle, which is said to make coffee that tastes like it was brewed in a moka pot.

#66: Post by **Bob_McBob** » September 30th, 2023, 1:50 pm

All true lever machines are piston machines, but not all piston machines are lever machines. By definition, a lever machine needs to have a physical lever of some sort that provides the driving force to the piston. We can get more nuanced discussion like how a rotating crank, linear actuator operating an internal lever, etc. is technically a lever, but I doubt there will ever be any consensus on the exact boundary. It's probably better to just move away from informally using "lever machine" to describe the broader class of piston-driven espresso machines.

#67: Post by **mrgnomer** » September 30th, 2023, 2:28 pm

I think defining a lever should be more a physical taxonomy thing than a linguistic symantics one. There needs to be a consensus about what defines a lever and maybe a branching out from say the Family of Lever to different Genus and Species.

What defines a lever? A manually controlled arm sticking out? That definitely identifies one. But what inside makes a lever different from other espresso machines like e61 or saturated grouphead pump driven machines? And how does that difference distinguish it mechanically relative to things like extraction parameter control from other types espresso machines?

#68: Post by **ira** » September 30th, 2023, 4:51 pm

But what inside makes a lever different from other espresso machines like e61 or saturated grouphead pump driven machines?

Personally, I would consider this not part of the discussion. The lever that makes it a lever machine is a physical thing and the fact that it may or may not brew better espresso has nothing to do with it's being a lever or not.

September 30th, 2023, 5:01 pm

I rather disagree. The mounting popularity of lever machines, along with powered machines with lever-like properties, has nothing to do with their appearance and everything to do with their performance.

There have always been collectors; and collectors are going to be engagged with the physical properties of the machines. But the audience for these collectors is not interested early steam espresso machines, nor curious stovetops, nor in 1970s and 1980s pump machines, etc., etc., but in lever machines. The many new releases of lever and lever like machines is also not about their appearance or physical structure.

All the renewed interest is about the functional properties of levers, in how they make shots and how those shots taste. If it weren't for that, levers would be what they were twenty years ago, collection curios gathering dust.

#70: Post by **donn** » September 30th, 2023, 5:31 pm

If you make a new machine that produces espresso shots indistinguishable from a lever machine, is it therefore a lever machine? No.

If I have a spring lever espresso machine that makes terrible espresso, is it a lever machine? Yes.

People may be interested in lever machines for whatever reason. What comes out of them, how they look on the counter, anything. It's immaterial to the definition.