philosophy of science

Metrology and the Press Room, Twickenham

Press Room coffee Twickenham

The arrival of the pour over at the Press Room, Twickenham.

It is not often that I have an errand to run in Twickenham, but when one popped up just two weeks after reading Brian’s Coffee Spot review of The Press Room, it was obvious where we were going to have a coffee. The Press Room serves pour over coffees (along with a good selection of other drinks). It is always great to find somewhere that serves pour overs well and so I had no hesitation in ordering a Nicaraguan “Los Altos” prepared by V60. Hot chocolate was available as white, milk or dark chocolate and there were a number of alternative non-dairy milks on offer as well as a large variety of tea. A lovely feature of The Press Room is that they offer suspended coffees, the idea being that you buy a coffee now for someone later who may not otherwise be able to afford one. The total number of coffees (given/claimed) is recorded on a blackboard behind the counter. It was nice to see that at the time of our visit 800+ coffees had been paid forward (and just less than 800 claimed), suggesting that the Press Room is having a positive effect on its local community.

clock wall Twickenham coffee

The large clock on the wall at The Press Room in Twickenham.

A great thing about ordering a pour over is watching as the barista expertly prepares your coffee, taking the time to do this properly. To be fair, this is part of the reason that finding a café serving pour-overs is becoming more difficult. After a while, the coffee was brought over to our table together with a bowl ready for me to place the filter cone on it when I was ready to enjoy the coffee. After taking the obligatory photograph, and pondering when would be the best time to remove the filter from the top of the mug and place it onto the empty bowl, the clock next to us took our attention. It is a large time piece that dominates this corner of the room. It is revealing to consider how the accuracy and availability of clocks have changed the way we live as a society.

Considering measurement (of time and other things), I used to be in this area more frequently a few years ago when I worked on a project in collaboration with the National Physical Laboratory (which is down the road, on the same bus route that Brian’s Coffee Spot notes takes you to a few good cafés). Partly, NPL’s work is to ensure that we know how to measure things properly. Take the pour over I enjoyed at The Press Room. A known amount (perhaps 12 g) of coffee was weighed out before 200 g of water was poured slowly over the coffee. But how do you know that the 12 g measured at Press Coffee is the same 12 g as you measure at home? And while perhaps it may not be critical for the coffee culture (even the most extreme home-brewer does not need to know the amount of coffee they are using to the nearest 0.000 002%), knowing accurately how heavy something is can be extremely important. Hence the need for a standard kilogram (and a standard metre, second, Candela etc) so that we have a way of knowing that what you call a kg is the same as what I call a kg.

coffee bowl pour over

The coffee that escaped! But was it a measure of my patience or hesitation?

Oddly, the kilogram is the last fundamental unit still defined with reference to a physical object (the other fundamental units are seconds, metres, Kelvin, Amperes, Moles, Candelas). The kilogram reference block is a PtIr alloy kept at the International Bureau of Weights and Measures near Paris. However all this may change next year depending on a decision due in November 2018. If all goes to plan, from May 2019 all units will be defined with respect to natural constants such as the speed of light etc. For the kilogram, this has meant measuring mass relative to a magnetic force generated by a coil of wire in a device known as a Kibble balance. In this way, the kg can be defined with respect to Planck’s constant and an era in which we measured substances relative to known objects will end.

On a day to day level though, how much do these things matter to us? Sometimes the way we measure things affects how we view them (and therefore what questions we ask next). Take for example temperature. We are used to measuring degrees of ‘hot’, so on the centigrade scale 0ºC is the freezing point of water and 100ºC is the boiling point. But it wasn’t always this way. Celsius devised his original scale to measure degrees of cold so 0º was the boiling point of water and 100º was the freezing point (you can read more about that story here). It is arguable that changing to measuring degrees of ‘hot’ enabled us to more easily conceptualise the idea of heat as energy and the field of thermodynamics. Certainly for a while, considering the idea of ‘degrees of cold’ meant that some looked for a substance of ‘cold’ called “frigorific“¹. There’s a similarity here with the coffee at The Press Room, was the amount of coffee in the bowl used to hold the filter after I removed it from the mug a measure of my impatience before trying the coffee or my hesitation at testing the coffee? How we ask that question affects how we view the coffee and the café (for reference, I would take the positive interpretation: the amount of coffee in the bowl measures my impatience; I was eager to try the coffee).

droplets on the side of a mug

Condensation on the side of the mug. These droplets can reveal many aspects of physics, which do you think about?

Partly this suggests some of the ways in which language, and philosophy, underpin all science. It certainly suggests one further connection with this bright and comfortable café. Erich Fromm in “To have or to be”² considered an interesting linguistic usage that reveals our way of being. Do we “have an idea”, or do we “think”? Are we consumers or people with experiences? Do we wish to have, to acquire, to consume or do we wish to exist, to be. Our language affects how we perceive the world which in turn changes the language we use about it. Linguistically, depending on how we interpret the cafe’s name “The Press Room”, we either have a café that offers a space to read the latest news or one that is reflective of the coffee brewing process (specifically espresso); a space to get up to date or one in which to contemplate? The symbol of the café visible in the frontage of the shop and on the mugs suggests the latter, but maybe it is something we need to experience to truly know?

¹Inventing Temperature, Hasok Chang, Oxford University Press, 2008

²To have or to be, Erich Fromm, Jonathan Cape, 1978

The Press Room is at 29 London Road, TW1 3SW

What is a good coffee?

Sun-dog, Sun dog

A photo to suggest happiness? Spotting sun dogs makes me happy.

A few weeks ago, an opinion piece appeared in a UK newspaper with the title “Scientists find nirvana as hard to explain as to attain”. The article was about the launch of a course, endorsed by the Dalai Lama, by the group ‘Action for Happiness‘ and the release that week of the Office of National Statistics League table of personal well-being. While happiness and well-being are both evidently things that we want to encourage, what do we mean by quantifying well-being into a league table?

It seems to be part of what can be a tendency to ‘scientise’ aspects of our lives and experience, aspects that are clearly, when we think about them, not described by science. Coffee is not immune from this. Studies have been made of how we feel about drinking our coffee based on whether we drink coffee for pleasure or for the caffeine kick. Why is it that we feel the need to quantify something in order to demonstrate that we have an understanding of it? Does labelling something as ‘scientific’ give it greater credibility?

As described elsewhere, part of the thinking behind Bean Thinking is to explore the beauty and the connectedness that an appreciation of the science in a coffee cup can give us. But there is an important corollary to this. It is to celebrate the contribution of those other aspects of our thinking that allow us to appreciate beauty: Art, literature, history. Beauty is not a quantity that can be defined scientifically (although we all seem to have a mutual appreciation of beauty and, surprisingly often, of what is beautiful). Happiness is similar. We have an understanding of what happiness is but a quantitative evaluation of happiness eludes us.

good coffee, nun mug, Ritzenhoff

How would you define a good coffee?

In hindsight it seems that, entirely unintentionally, the tagline of Bean Thinking captured both of these aspects of meaning. “Where entertaining science meets good coffee“: Hopefully it is fairly easy to find the science on the website but good coffee? What do we mean by ‘good’. Is my version of “good” coffee the same as yours? Is ‘good’ in this context something that can be quantified (acidity, aroma etc) or something more, a word that incorporates aspects of the living conditions of the farmers who grow the coffee and the workers who pick the cherries at harvest time? In attempting to understand what is a ‘good coffee’ we may be tempted to define good as being a coffee having certain properties, a pH around X, a quantity of caffeine around Y and a fraction of 2-furfurylthiol (a chemical which contributes to coffee’s pleasurable aroma) of at least Z. This is a route that will lead us to instant!

But joking aside, by narrowly defining the word ‘good’ so that we feel that our understanding of it is scientific and therefore irrefutable, we have lost what we originally meant by good. Science is an important tool, one that helps us to understand (and to control) the world around us but it is not a philosophy. We can never use science to define a ‘good coffee’ in a way that we would all recognise as a good definition of good. Of course science can help us to decide aspects of a good coffee (the pH, the caffeine content etc. all contribute to a good cup) but we cannot use it, of itself, to define a good cup. The same must go for happiness and other aspects of our lives (can we measure a good school by its position in a league table for example?). We must always be on our guard against over-stating the proper limits of science. We cannot use it in defence of a metaphysical position. The strength of science lies in its being a key part of our tool box for examining and understanding the world.

Fish in a tank

Fish in a tank

Admitting that aspects of our definition of a good coffee are qualitative, arguable or even “subjective” does not devalue the meaning of the word good. The same applies to happiness and many other areas. Quantifying something can mean that we understand it less. Midgley has an interesting analogy in this context of the roles of different areas of our thought:

[An image that is helpful] is that of the world as a huge aquarium. We cannot see it as a whole from above, so we peer in at it through a number of small windows. Inside, the lighting is not always good and there are rocks and weeds for the inhabitants to hide in. Is that the same fish coming out that we saw just now over there? And are those things stones or starfish? We can eventually make quite a lot of sense of this habitat if we patiently put together the data from different angles. But if we insist that our own window is the only one worth looking through, we shall not get very far.“*

According to the ‘quantitative’ measurement of well-being in the ONS survey, London is a relatively miserable place. The Action for Happiness group runs a Happy Cafe network which includes two London cafes: The Canvas and The Skittle Alley Coffee & Pantry. I have no idea as to whether such cafes can help us to live happier and more meaningful lives. I do know however that I won’t be able to find out whether they do so ‘scientifically’. I also know, that slowing down and spending five minutes contemplating my coffee, wherever I am, will help me to develop into a more rounded person. I am unable to define (scientifically) what I mean by rounded.

If you have a good definition of good, why not share it in the comments section below. Alternatively, if you are enjoying five minutes (or more) in a great cafe with something about it that is interesting to notice, why not think about writing it as a cafe-physics review?

* “The Myths We Live By”, Mary Midgley, was published by Routledge Classics, 2004