Berkeley

Seeing the unseen at Scarlett, Angel

Coffee Angel, Scarlett, roasters, coffee in Islington
Coffee at Scarlett, Angel

Although first alerted to Scarlett coffee in Angel by Double Skinny Macchiato last summer, we managed to visit during the one week of their summer holiday (and so we revisited Katsute100 around the corner instead). Nonetheless, it remained on the list and a few weeks ago we turned up for a mid-afternoon coffee at this inconspicuous looking venue on a side street just around the corner from Angel tube.

The roaster at the back of the cafe forms an immediate impression. With the large, communal table at the front of the cafe, backed by stairs leading up to the roaster, this is a place where coffee is taken seriously. The counter (on the left as you enter) offered a range of cakes and edibles but having recently come from lunch in Chapel Market, we passed on this on this occasion. Above the counter there were about 5 lights hanging down forming what looked like a giant Newton’s Cradle. Just too high for me to reach unfortunately.

I enjoyed my long black as I started to take in the surroundings of this cafe. Various people and regulars came and went, suggesting that this is a friendly local haunt for many. Noticing the number of different roasted coffee beans for retail, it was clear that this is a venue that you could return to for a different coffee experience each time. Each time exploring an aspect of the flavour of the coffee and building on the experience of coffee tasting that you have enjoyed before. It is definitely on the list for a repeat visit.

Interior Scarlett
One of the light fittings at Scarlett in Angel. Cube outlines drawn on paper can form an optical illusion where you can’t work out if the cube is coming out at you or going into the paper.

Above our heads, the lights were framed by the outline of a cube. Fantastic for optical illusions, these cubes offer us an opportunity to think about how we perceive depth and direction; how our eyes work and perhaps, more fundamentally, what it even means to see an object (as with Berkeley’s “New Theory of Vision”). Then, while looking through the menu, it became clear that here too there was an optical illusion of sorts. For the price list was not written on the board so much as cut out of it (see the photo below). The price you could read off the menu was, in some sense, precisely the information that was not actually on the board. Our brain makes patterns of that which we don’t see and, together with our assumptions about what should be there, we form an idea of the price we have to pay.

It is a similar thing with many algorithms in use around us now. Such tools can be immensely helpful, offering us suggestions for coffees we may like to try (based on our buying habit) or routes that we may like to take to get us to our destination. And yet, are there problems hidden in the assumptions that some of these algorithms make? What information are we getting based on elements in the programme that we do not see?

In her excellent book “Weapons of Math Destruction”, Cathy O’Neil explores some of the more dangerous ways that our biases and assumptions (particularly those that we don’t see in ourselves) can impact the results of algorithms that have been written to optimise processes from the sorting of job applications to determining the length of time a given convicted criminal will serve for an offence. In an example relevant for cafes, O’Neil related an example of how Starbucks had used an algorithm to determine which baristas and managers should work which hours, including who should close the shop at night and who should open it in the morning.

Scarlett menu
The menu at Scarlett. Apart from the filter coffee, the prices and information for each coffee is revealed by what is absent from the board rather than what is printed onto it.

The algorithm was programmed to calculate the most efficient use of the cafe’s time and money, specifically prioritising the profit that the company made. One measure of this was “revenue per employee hour”. This had the consequence that staff members were frequently in a position where they were told that they had to do both the (late night) closing and (early morning) opening of the shop and were given very few days notice of this expectation. Clearly this impacted the lives of their staff and affected their ability to arrange child care, support themselves through further education and other consequences. Eventually Starbucks was forced to amend this algorithm but change comes hard: how do you ask a computer to measure “fairness” to an employee (a subjective term) when you can use revenue per employee hour which is measurable, quantifiable and therefore ‘accurate’?

Perhaps you think that the link back to Scarlett here is obvious: That if you choose to drink your coffee in friendly neighbourhood cafes where cafe owners and baristas work to patterns formed by encounter rather than algorithm it would be better than a place which is run assuming all workers are cogs in a profit machine? Perhaps. But the link back to Scarlett in my mind is not that at all.

If you look at the front of Scarlett, or its webpage, and assume that the pink bird is a funny looking flamingo, you may make a series of assumptions about what you think the cafe will be like and why the owners have a bird on their front door. If you found out that the bird was actually a Scarlet Ibis and associated with the coffee growing regions of South America, your ideas about the cafe and the owners may be different. For a general customer, looking for somewhere to enjoy a great coffee, perhaps these assumptions and ideas do not matter so much. But if we are ever in a position to feed our assumptions into an algorithm, these hidden (to our own conscious) assumptions could matter a great deal.

Scarlett is at 30 Duncan Street, N1 8BW

“Weapons of Math Destruction – how big data increases inequality and threatens democracy” by Cathy O’Neil, Penguin Books, 2016

Getting some perspective at Skylark, Wandsworth

Skylark Wandsworth

A sunny day at the Skylark on Wandsworth Common

It is late spring in the northern hemisphere and when the weather is fine, what better way to spend it than with a coffee in the middle of Wandsworth Common at the Skylark Cafe? With a number of tables outside and, if the weather turns bad, several more tables inside, Skylark is a lovely place to spend some time while wandering in West London. On the day that we were there, Skylark was frequented by a large number of families however, it was a Saturday afternoon and so it is quite possible that on a week-day it will be a bit quieter. The coffee is roasted by Caravan and they have an interesting array of cakes inside, but it was the plants on the tables outside that caught my attention. Each table had a pot of thyme on it, but the thyme smelled of lemon. Perhaps it was lemon thyme, but something that looks like one thing and smells of another is a nice introduction to this week’s Daily Grind which is all about appearances, reality and perspective.

The thyme was growing in a metal flower pot which reflected the wooden table top. From the photo (below, left), it is clear that the pot is cylindrical but if we stop and think about it, how do we actually know that? The image is two dimensional, no third dimension is possible through a computer screen. What clues in the picture tell you that the pot is cylindrical? The bending of the lines of the table top? This is a pattern that we have learned, we have found from experience that something that is circular will bend straight lines in this way.

perspective, flower pot

What shape is the flower pot?

How we see things and what we think we are seeing was a subject that bothered George Berkeley (1685-1753). How can you know that anything external to yourself is real? Everything you touch, everything you see, hear, taste or smell is, ultimately, a response in your brain to a stimulus. It is not easy to prove that anything ‘outside oneself’ really exists. Indeed, Berkeley argued for the theory that what was ‘real’ was only the sensations in your mind. The theory was famously challenged by Dr Samuel Johnson (1709-1784) who used to drink coffee at the Turks Head in Gerrard St. in what is now Chinatown. Johnson hurt himself by kicking a stone, while saying of Berkeley’s theory: “I refute it thus“. Does Johnson’s sore foot really refute the theory though? How can we avoid Berkeley and find our world again?

Writing about science at the turn of the twentieth century, Pierre Duhem (1861-1916) argued that “All the time we view scientific theory as an attempt at an explanation, we will be limited in what we consider an acceptable explanation by our metaphysical beliefs. Only by accepting that theory is in fact a description, a cataloguing, do we free ourselves from all but the primary metaphysical belief that the world exists“. In other words, in order to ‘do’ science we have to rely on (at least) two beliefs a) that the world outside exists, b) it is consistent, that is, governed by laws that are knowable. Neither of these premises can be ‘scientifically’ proven, instead they lie at the base of our belief system, even if we do tend to take them for granted. It is far easier after all to live in the world, if we assume that it exists.

Americano, Caravan coffee, Skylark, Wandsworth

Coffee at the Skylark

None of this should stop us doing science. Whatever we are investigating with our experimental (or theoretical) tools it is beautiful and the more that we understand the mathematics that describe the world, the more beautiful the world outside becomes. I cannot prove, scientifically, that the world outside exists, I could possibly argue that it does based on philosophical ideas but I will never be able to prove it. I understand that the pot on the table at Skylark is a three dimensional cylinder because of the way that the light is  bent on reflection and from my, admittedly intuitive, understanding of perspective. Perhaps we also need some perspective in appreciating what we can, and cannot, prove with science.

 

Skylark Cafe is on Wandsworth Common.

Quote taken from “The Aim and Structure of Physical Theory”, Pierre Duhem, 1910.