I thank all of the friends who sent me birthday greetings on Facebook this year. [But see note at end.] One friend noted that I was not likely to see his birthday greeting, since I do not pay attention to Facebook these days. I usually do not pay attention; but since so many friends apparently continue to use that medium, I have not closed my account. I recently posted on Facebook a couple of photographs showing a friend from Washington who was visiting Istanbul. These photographs were “liked” by friends of that person or of me. Thus I suppose I used Facebook for its best purpose.

Still my general concern remains. If I look at Facebook, it decides what I am going to see; if I post on Facebook, it decides who is going to see what I post. These decisions are not based on knowledge of me or anybody else as an individual. They are not properly decisions at all: they are not choices made as a result of thinking. They are occurrences resulting from the implementation of a computer program or “algorithm.”

That, in brief, is my objection to Facebook. If now something else is seeking your attention, you may stop reading here and go off in pursuit of it. In the sequel below, I shall only elaborate on the general objection.

Implementation of an algorithm is not thinking: it is the cessation of thinking. There is not necessarily anything wrong with this. I am going to give a mathematical example. At this point, some writers would tell their readers how far ahead to skip to avoid the mathematics. Imitating those writers, I tell you too: you can skip ahead to the paragraph that begins with “Algorithms.” However, I think my mathematical example is illustrative of an important point. Some people treat mathematics with a kind of awe that it does not deserve. It is a tool, which like any tool can be used well or ill. If I ask you to find the greatest common divisor of 610 and 987, and if for some reason you want to obey me, then you may think about the problem just enough to observe that the so-called Euclidean algorithm will solve it. The algorithm is ancient, being described at the beginning of Books VII and X of Euclid’s Elements, around 300 bce. You can apply the algorithm mechanically, saving your energy for more important matters. So you proceed:

987 = 610 + 377,
610 = 377 + 233,
377 = 233 + 144,
233 = 144 + 89,
144 = 89 + 55,
89 = 55 + 34,
55 = 34 + 21,
34 = 21 +13,
21 = 13 + 8,
13 + 8 + 5,
8 = 5 + 3,
5 = 3 + 2,
3 = 2 + 1.

Thus, as we say, the greatest common divisor of 987 and 610 is 1; or as Euclid concludes in his Proposition VII.1, the two numbers are prime to one another.

As an alternative, you might decide to take a chance on actually factorizing the given numbers. Here you would rely on the so-called Fundamental Theorem of Arithmetic, which apparently nobody stated before Gauss in the Disquisiones Arithmeticae of 1801. Euclid proved a special case in his Proposition IX.14, but his proof does not generalize. For the present problem, you may find

610 = 2 × 5 × 61,
987 = 3 × 7 × 47.

All of these factors being prime, but unshared, the original numbers 610 and 987 are prime to one another, and so their greatest common divisor is 1.

The numbers 610 and 987 are in fact the 15th and 16th Fibonacci numbers. If you happened to be in a position to notice this, you could conclude instantly that the numbers were prime to one another, without going through the steps of the Euclidean algorithm—in this case, the 13 steps given above. On the other hand, it takes just 4 steps of the Euclidean algorithm to find that 437 and 899 are coprime, while factorizing by hand would be tedious, as these numbers are 19 × 23 and 29 × 31.

Algorithms are useful, but algorithms as such do not tell you just when they are going to be useful. You have to decide that—or take a guess.

The Facebook algorithm, which decides what people are going to be shown or notified about—this algorithm is certainly created by thinking. But this thinking is about how to get people to spend as much time as possible looking at Facebook and at Facebook’s advertisers.

Magazine readers do not like starting a story and, after reading for a while, being told to turn to page one hundred and something. Writers do not like it either, for they think the interruption disturbs the reader and they have besides an uneasy fear that sometimes he will not take the trouble and so leave the story unfinished. There is no help for it. Everyone should know that a magazine costs more to produce than it is sold for, and could not exist but for the advertisements. The advertisers think that their announcements are more likely to be read if they are on the same page as the matter which they modestly, but often mistakenly, think of greater interest. So in the illustrated periodicals it has been found advisable to put the beginning of a story or an article, with the picture that purports to illustrate it, at the beginning and the continuation with the advertisements later on.

Neither reader nor writers should complain. Readers get something for far less than the cost price and writers are paid sums for their productions which only the advertisements render possible. They should remember that they are only there as bait. Their office is to fill blank spaces and indirectly induce their readers to buy motor accessories, aids to beauty and join correspondence courses [sic]. Fortunately this need not affect them. The best story from the advertisers’ standpoint (and they make their views felt on this question) is the story that gives readers most entertainment…

Note added several minutes after publication: I set out to put a link to this article as a comment on the message of every birthday greeting that I received. I got a warning from Facebook:

It looks like you’re using this feature in a way it wasn’t meant to be used. Please slow down, or you could be blocked from using it.

I suppose Facebook thinks I am spamming people. You should be protected from me. I should post a link to my article once, and you may or may not see it, as Facebook decides.

1. Bill

I disagree with your notion of Facebook as having the ability to take away your will. I think, and my long experience bears me out, that I am notified about everything my “close” friends, except for those things those “close” friends might exclude me from. Similarly, I do not have to look at the posts of others, unless I want to. Finally, I can limit what I post to a narrow audience, or to the whole world. Your example of the algorithm in Euclid doesn’t really do me much good. It is not an example from common experience, other than perhaps David, your common experience. So your stated reasons for denying us the pleasure of your company on Facebook do not withstand scrutiny, and It would be appreciated if you would come round and take 30 minutes to tweak your account.

Also, thanks for a wonderful post.

• Posted March 19, 2015 at 1:38 pm | Permalink | Reply

Bill, the contents of the Facebook “news” feed are not under your direct control. You can influence contents by who your “friends” are and by what you click on, but you don’t know exactly what the results of these actions will be. Neither is any other human being deciding what will be on your “news” feed; but an algorithm “decides.” The algorithm is written by human beings, but not in your interest: it is written to get you to spend as much time as possible on Facebook. I have spent a lot of time on Facebook in the last few years; now I have decided it is best to spend my time elsewhere.

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