Zero in Greek mathematics

I recently read The Nothing That Is: A Natural History of Zero by Robert M. Kaplan. Zero is an important concept in mathematics. But where did it come from?

The Babylonian zero

From around 2000 BC, the Babylonians used a positional number system with base 60. Initially a space was used to represent zero. Vertical wedges mean 1, and chevrons mean 10:

This number (which we can write as 2 ; 0 ; 13) means 2 × 3600 + 0 × 60 + 13 = 7213. Four thousand years later, we still use the same system when dealing with angles or with time: 2 hours, no minutes, and 13 seconds is 7213 seconds.

Later, the Babylonians introduced a variety of explicit symbols for zero. By 400 BC, a pair of angled wedges was used:

The Babylonian zero was never used at the end of a number. The Babylonians were happy to move the decimal point (actually, “sexagesimal point”) forwards and backwards to facilitate calculation. The number ½, for example, was treated the same as 30 (which is half of 60). In much the same way, 20th century users of the slide rule treated 50, 5, and 0.5 as the same number. What is 0.5 ÷ 20? The calculation is done as 5 ÷ 2 = 2.5. Only at the end do you think about where the decimal point should go (0.025).

Greek mathematics in words

Kaplan says about zero that “the Greeks had no word for it.” Is that true?

Much of Greek mathematics was done in words. For example, the famous Proposition 3 in the Measurement of a Circle (Κύκλου μέτρησις) by Archimedes reads:

Παντὸς κύκλου ἡ περίμετρος τῆς διαμέτρου τριπλασίων ἐστί, καὶ ἔτι ὑπερέχει ἐλάσσονι μὲν ἤ ἑβδόμῳ μέρει τῆς διαμέτρου, μείζονι δὲ ἢ δέκα ἑβδομηκοστομόνοις.

Phonetically, that is:

Pantos kuklou hē perimetros tēs diametrou triplasiōn esti, kai eti huperechei elassoni men ē hebdomō merei tēs diametrou, meizoni de ē deka hebdomēkostomonois.

Or, in English:

The perimeter of every circle is triple the diameter plus an amount less than one seventh of the diameter and greater than ten seventy-firsts.

In modern notation, we would express that far more briefly as 10/71 < π − 3 < 1/7 or 3.141 < π < 3.143.

The Greek words for zero were the two words for “nothing” – μηδέν (mēden) and οὐδέν (ouden). Around 100 AD, Nicomachus of Gerasa (Gerasa is now the city of Jerash, Jordan), wrote in his Introduction to Arithmetic (Book 2, VI, 3) that:

οὐδέν οὐδενί συντεθὲν … οὐδέν ποιεῖ (ouden oudeni suntethen … ouden poiei)

That is, zero (nothing) can be added:

nothing and nothing, added together, … make nothing

However, we cannot divide by zero. Aristotle, in Book 4, Lectio 12 of his Physics tells us that:

οὐδὲ τὸ μηδὲν πρὸς ἀριθμόν (oude to mēden pros arithmon)

That is, 1/0, 2/0, and so forth make no sense:

there is no ratio of zero (nothing) to a number

If we view arithmetic primarily as a game of multiplying, dividing, taking ratios, and finding prime factors, then poor old zero really does have to sit on the sidelines (in modern terms, zero is not part of a multiplicative group).

Greek calculation

For business calculations, surveying, numerical tables, and most other mathematical calculations (e.g. the proof of Archimedes’ Proposition 3), the Greeks used a non-positional decimal system, based on 24 letters and 3 obsolete letters. In its later form, this was as follows:

Units Tens Hundreds
α = 1 ι = 10 ρ = 100
β = 2 κ = 20 σ = 200
γ = 3 λ = 30 τ = 300
δ = 4 μ = 40 υ = 400
ε = 5 ν = 50 φ = 500
ϛ (stigma) = 6 ξ = 60 χ = 600
ζ = 7 ο = 70 ψ = 700
η = 8 π = 80 ω = 800
θ = 9 ϙ (koppa) = 90 ϡ (sampi) = 900

For users of R:

to.greek.digits <- function (v) { # v is a vector of numbers
  if (any(v < 1 | v > 999)) stop("Can only do Greek digits for 1..999")
  else {
    s <- intToUtf8(c(0x3b1:0x3b5,0x3db,0x3b6:0x3c0,0x3d9,0x3c1,0x3c3:0x3c9,0x3e1))
    greek <- strsplit(s, "", fixed=TRUE)[[1]]
    d <- function(i, power=1) { if (i == 0) "" else greek[i + (power - 1) * 9] }
    f <- function(x) { paste0(d(x %/% 100, 3), d((x %/% 10) %% 10, 2), d(x %% 10)) }
    sapply(v, f)
  }
}

For example, the “number of the beast” (666) as written in Byzantine manuscripts of the Bible is χξϛ (older manuscripts spell the number out in words: ἑξακόσιοι ἑξήκοντα ἕξ = hexakosioi hexēkonta hex).

This Greek system of numerals did not include zero – but then again, it was used in situations where zero was not needed.

Greek geometry

Most of Greek mathematics was geometric in nature, rather than based on calculation. For example, the famous Pythagorean Theorem tells us that the areas of two squares add up to give the area of a third.

In geometry, zero was represented as a line of zero length (i.e. a point) or as a rectangle of zero area (i.e. a line). This is implicit in Euclid’s first two definitions (σημεῖόν ἐστιν, οὗ μέρος οὐθέν = a point is that which has no part; γραμμὴ δὲ μῆκος ἀπλατές = a line is breadthless length).


In the Pythagorean Theorem, lines are multiplied by themselves to give areas, and the sum of the two smaller areas gives the third (image: Ntozis)

Graeco-Babylonian mathematics

In astronomy, the Greeks continued to use the Babylonian sexagesimal system (much as we do today, with our “degrees, minutes, and seconds”). Numbers were written using the alphabetic system described above, and at the time of Ptolemy, zero was written like this (appearing in numerous papyri from 100 AD onwards, with occasional variations):

For example, 7213 seconds would be β ō ιγ = 2 0 13 (for another example, see the image below). The circle here may be an abbreviation for οὐδέν = nothing (just as early Christian Easter calculations used N for Nulla to mean zero). The overbar is necessary to distinguish ō from ο = 70 (it also resembles the overbars used in sacred abbreviations).

This use of a circle to mean zero was passed on to the Arabs and to India, which means that our modern symbol 0 is, in fact, Graeco-Babylonian in origin (the contribution of Indian mathematicians such as Brahmagupta was not the introduction of zero, but the theory of negative numbers). I had not realised this before; from now on I will say ouden every time I read “zero.”


Part of a table from a French edition of Ptolemy’s Almagest of c. 150 AD. For the angles x = ½°, 1°, and 1½°, the table shows 120 sin(x/2). The (sexagesimal) values, in the columns headed ΕΥΘΕΙΩΝ, are ō λα κε = 0 31 25 = 0.5236, α β ν = 1 2 50 = 1.0472, and α λδ ιε = 1 34 15 = 1.5708. The columns on the right are an aid to interpolation. Notice that zero occurs six times.


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Eight Greek inscriptions

I love ancient inscriptions. They provide a connection to people of the past, they provide an insight into how people thought, and they demonstrate how the experience of writing has changed over the past five thousand years or so. Here are eight Greek inscriptions and documents that interest me – some historical, some religious, and one mathematical.


Six of the eight inscriptions

1. The inscription that is no longer there, 480 BC

Our first inscription was inscribed at the site of the Battle of Thermopylae (480 BC), where Leonidas and his 300 Spartans (plus several thousand allies) died trying to hold off a vastly superior Persian army. The inscription no longer exists (though there is a modern copy at the site), but the wording has been preserved by Herodotus (Histories 7.228.2):

Ω ΞΕΙΝ ΑΓΓΕΛΛΕΙΝ
ΛΑΚΕΔΑΙΜΟΝΙΟΙΣ ΟΤΙ ΤΗΔΕ
ΚΕΙΜΕΘΑ ΤΟΙΣ ΚΕΙΝΩΝ
ΡΗΜΑΣΙ ΠΕΙΘΟΜΕΝΟΙ.

Phonetically, that reads:

Ō ksein’, angellein
Lakedaimoniois hoti tēide
keimetha, tois keinōn
rhēmasi peithomenoi.

I’ve always thought that there was a degree of sarcasm in this laconic epigram – after all, the Spartans had declared war on the Persians (rather informally, by throwing the Persian ambassadors down a well), but then stayed home, leaving Leonidas and his personal honour guard (plus the allies) to do the actual fighting. My (rather free) personal translation would therefore be:

Go tell the Spartans,
Stranger passing by,
We listened to their words,
And here we lie.


The battle of Thermopylae, 480 BC (illustration: John Steeple Davis)

2. The Rosetta Stone, 196 BC

The rich history of the Rosetta Stone has always fascinated me (and I made a point of seeing the Stone when I visited the British Museum). The Stone records a decree of 196 BC from Ptolemy V, inscribed using three forms of writing – Egyptian hieroglyphs, Egyptian demotic script, and a Greek translation. The Stone was therefore a valuable input to the eventual decoding of Egyptian hieroglyphs. Romance practically drips off the Stone.


The Rosetta Stone in the British Museum (photo: Hans Hillewaert)

3. The Theodotus inscription, before 70 AD

The Theodotus inscription in Jerusalem was located in a 1st century synagogue near the Temple (this dating is generally accepted). It reads as follows (with [square brackets] denoting missing letters):

ΘΕΟΔΟΤΟΣ ΟΥΕΤΤΕΝΟΥ ΙΕΡΕΥΣ ΚΑΙ
ΑΡΧΙΣΥΝΑΓΩΓΟΣ ΥΙΟΣ ΑΡΧΙΣΥΝ[ΑΓΩ]
Γ[Ο]Υ ΥΙΟΝΟΣ ΑΡΧΙΣΥΝ[Α]ΓΩΓΟΥ ΩΚΟ-
ΔΟΜΗΣΕ ΤΗΝ ΣΥΝΑΓΩΓ[Η]Ν ΕΙΣ ΑΝ[ΑΓ]ΝΩ-
Σ[Ι]Ν ΝΟΜΟΥ ΚΑΙ ΕΙΣ [Δ]ΙΔΑΧΗΝ ΕΝΤΟΛΩΝ ΚΑΙ
ΤΟΝ ΞΕΝΩΝΑ ΚΑ[Ι ΤΑ] ΔΩΜΑΤΑ ΚΑΙ ΤΑ ΧΡΗ-
Σ[Τ]ΗΡΙΑ ΤΩΝ ΥΔΑΤΩΝ ΕΙΣ ΚΑΤΑΛΥΜΑ ΤΟΙ-
Σ [Χ]ΡΗZΟΥΣΙΝ ΑΠΟ ΤΗΣ ΞΕ[Ν]ΗΣ ΗΝ ΕΘΕΜΕ-
Λ[ΙΩ]ΣΑΝ ΟΙ ΠΑΤΕΡΕΣ [Α]ΥΤΟΥ ΚΑΙ ΟΙ ΠΡΕ-
Σ[Β]ΥΤΕΡΟΙ ΚΑΙ ΣΙΜΩΝ[Ι]ΔΗΣ.

In translation:

Theodotus, son of Vettenus [or, of the gens Vettia], priest and
archisynagogue [leader of the synagogue], son of an archisynagogue,
grandson of an archisynagogue, built
the synagogue for the reading of
the Law and for teaching the commandments;
also the hostel, and the rooms, and the water
fittings, for lodging
needy strangers. Its foundation was laid
by his fathers, and the
elders, and Simonides.

The inscription is interesting in a number of ways. Along with other similar inscriptions, it demonstrates the existence of Greek-language synagogues in 1st Palestine. The title ἀρχισυνάγωγος (archisynagōgos) also occurs in the New Testament (nine times, starting at Mark 5:22), so is clearly a title of the time-period. Some scholars have suggested that Theodotos was a freed slave, who had made his fortune and returned from Italy to the land of his fathers (in which case there is a very slight possibility that the synagogue with the inscription might have been the “synagogue of the Freedmen” mentioned in Acts 6:9).


The Theodotus inscription in the Israel Museum, Jerusalem (photo: Oren Rozen)

4. The Delphi inscription, 52 AD


The Temple of Apollo at Delphi (photo: Luarvick)

The Delphi inscription is a letter of around 52 AD from the Roman emperor Claudius. It was inscribed on stone at the Temple of Apollo at Delphi (above), although it now exists only as nine fragments. Of particular interest is this line (see also the photograph below):

[IOU]ΝΙΟΣ ΓΑΛΛΙΩΝ Ο Φ[ΙΛΟΣ] ΜΟΥ ΚΑ[Ι ΑΝΘΥ]ΠΑΤΟΣ …

Phonetically, that reads:

[Jou]nios Galliōn ‘o ph[ilos] mou ka[i anthu]patos …

This is a reference to Lucius Junius Gallio Annaeanus, who was briefly proconsul (anthupatos) of the Roman senatorial province of Achaea (southern Greece) at the time:

Junius Gallio, my friend and proconsul …

This same anthupatos Gallio appears in the New Testament (Acts 18:12–17: “Γαλλίωνος δὲ ἀνθυπάτου ὄντος τῆς Ἀχαΐας …”), and therefore provides a way of dating the events described there.


One of the fragments of the Delphi inscription, highlighting the name ΓΑΛΛΙΩΝ = Gallio (photo: Gérard)

5. Papyrus Oxyrhynchus 29, c. 100 AD

I have written before about Papyrus Oxyrhynchus 29. It contains the statement of Proposition 5 of Book 2 of Euclid’s Elements, with an accompanying diagram (plus just a few letters of the last line of the preceding proposition). In modern Greek capitals, it reads:

ΕΑΝ ΕΥΘΕΙΑ ΓΡΑΜΜΗ
ΤΜΗΘΗ ΕΙΣ ΙΣΑ ΚΑΙ ΑΝ-
ΙΣΑ ΤΟ ΥΠΟ ΤΩΝ ΑΝΙ-
ΣΩΝ ΤΗΣ ΟΛΗΣ ΤΜΗΜ[ΑΤ]ΩΝ ΠΕΡΙΕΧΟΜΕΝΟΝ
ΟΡΘΟΓΩΝΙΟΝ ΜΕΤΑ Τ[Ο]Υ ΑΠΟ ΤΗΣ ΜΕΤΟΞΥ
ΤΩΝ ΤΟΜΩΝ ΤΕΤ[ΡΑ]ΓΩΝΟΥ ΙΣΟΝ ΕΣΤΙΝ
ΤΩ ΑΠΟ ΤΗΣ ΗΜΙΣΕΙ-
ΑΣ ΤΕΤΡΑΓΩΝΟΥ

However, the actual document (image below) uses “Ϲ” for the modern “Σ,” and “ω” for the modern “Ω”:

ΕΑΝ ΕΥΘΕΙΑ ΓΡΑΜΜΗ
ΤΜΗΘΗ ΕΙϹ ΙϹΑ ΚΑΙ ΑΝ-
ΙϹΑ ΤΟ ΥΠΟ ΤωΝ ΑΝΙ-
ϹωΝ ΤΗϹ ΟΛΗϹ ΤΜΗΜ[ΑΤ]ωΝ ΠΕΡΙΕΧΟΜΕΝΟΝ
ΟΡΘΟΓωΝΙΟΝ ΜΕΤΑ Τ[Ο]Υ ΑΠΟ ΤΗϹ ΜΕΤΟΞΥ
ΤωΝ ΤΟΜωΝ ΤΕΤ[ΡΑ]ΓωΝΟΥ ΙϹΟΝ ΕϹΤΙΝ
Τω ΑΠΟ ΤΗϹ ΗΜΙϹΕΙ-
ΑϹ ΤΕΤΡΑΓωΝΟΥ

This manuscript is important because, being from 75–125 AD, it dates to only four centuries after the original was written in 300 BC – most manuscripts of Euclid are twelve centuries or more after (in fact, it pre-dates the alterations made to the work by Theon of Alexandria in the 4th century AD). The manuscript also contains one of the oldest extant Greek mathematical diagrams. The text is identical to the accepted Greek text, except for two spelling variations and one one grammatical error (τετραγώνου for τετραγώνῳ on the last line, perhaps as the result of the mental influence of the preceding word in the genitive):

ἐὰν εὐθεῖα γραμμὴ
τμηθῇ εἰς ἴσα καὶ ἄνισα,
τὸ ὑπὸ τῶν ἀνίσων τῆς ὅλης τμημάτων περιεχόμενον ὀρθογώνιον
μετὰ τοῦ ἀπὸ τῆς μεταξὺ τῶν τομῶν τετραγώνου
ἴσον ἐστὶ τῷ ἀπὸ τῆς ἡμισείας τετραγώνῳ.

It is really just a geometric way of expressing the equality (x + y)2 = x2 + 2xy + y2, but in English it reads as follows:

If a straight line
be cut into equal and unequal [segments] (x + y + x and y),
the rectangle contained by the unequal segments of the whole (i.e. (x + y + x)y = 2xy + y2)
together with the square on the straight line between the points of section (+ x2)
is equal to the square on the half (= (x + y)2).

The proof of the proposition is missing, however, and there are no labels on the diagram. I suspect that the manuscript was a teaching tool of some kind (either an aide-mémoire or an exam question). Alternatively, it may have been part of an illustrated index to the Elements.


Papyrus Oxyrhynchus 29 (photo: Bill Casselman)

6. Rylands Library Papyrus P52, c. 140 AD

Papyrus P52 is a small fragment written in a similar style to Papyrus Oxyrhynchus 29, but is dated a few decades later (to around 140 AD). In modern Greek capitals, it reads:

ΟΙ ΙΟΥΔΑΙ[ΟΙ]· ΗΜΕ[ΙΝ ΟΥΚ ΕΞΕΣΤΙΝ ΑΠΟΚΤΕΙΝΑΙ]
ΟΥΔΕΝΑ. ΙΝΑ Ο Λ[ΟΓΟΣ ΤΟΥ ΙΗΣΟΥ ΠΛΗΡΩΘΗ ΟΝ ΕΙ]
ΠΕΝ ΣΗΜΑΙΝΩ[Ν ΠΟΙΩ ΘΑΝΑΤΩ ΗΜΕΛΛΕΝ ΑΠΟ]
ΘΝΗΣΚΕΙΝ. ΙΣ[ΗΛΘΕΝ ΟΥΝ ΠΑΛΙΝ ΕΙΣ ΤΟ ΠΡΑΙΤΩ]
ΡΙΟΝ Ο Π[ΙΛΑΤΟΣ ΚΑΙ ΕΦΩΝΗΣΕΝ ΤΟΝ ΙΗΣΟΥΝ]
ΚΑΙ ΕΙΠ[ΕΝ ΑΥΤΩ· ΣΥ ΕΙ O ΒΑΣΙΛΕΥΣ ΤΩΝ ΙΟΥ]
[Δ]ΑΙΩN;

The reverse side also has writing:

[ΒΑΣΙΛΕΥΣ ΕΙΜΙ. ΕΓΩ ΕΙΣ TO]ΥΤΟ Γ[Ε]ΓΕΝΝΗΜΑΙ
[ΚΑΙ (ΕΙΣ ΤΟΥΤΟ) ΕΛΗΛΥΘΑ ΕΙΣ ΤΟΝ ΚΟ]ΣΜΟΝ, ΙΝΑ ΜΑΡΤΥ-
[ΡΗΣΩ ΤΗ ΑΛΗΘΕΙΑ· ΠΑΣ Ο ΩΝ] ΕΚ ΤΗΣ ΑΛΗΘΕI-
[ΑΣ ΑΚΟΥΕΙ ΜΟΥ ΤΗΣ ΦΩΝΗΣ]. ΛΕΓΕΙ ΑΥΤΩ
[Ο ΠΙΛΑΤΟΣ· ΤΙ ΕΣΤΙΝ ΑΛΗΘΕΙΑ; Κ]ΑΙ ΤΟΥΤΟ
[ΕΙΠΩΝ ΠΑΛΙΝ ΕΞΗΛΘΕΝ ΠΡΟΣ] ΤΟΥΣ Ι[ΟΥ]
[ΔΑΙΟΥΣ ΚΑΙ ΛΕΓΕΙ ΑΥΤΟΙΣ· ΕΓΩ ΟΥΔ]ΕΜΙ[ΑΝ]
[ΕΥΡΙΣΚΩ ΕΝ ΑΥΤΩ ΑΙΤΙΑΝ].

Some clever detective work has identified the fragment as being from a manuscript of the New Testament gospel of John (John 18:31b–33 and 18:37b–38), permitting the reconstruction of the missing letters. The fragment is from the top inner corner of a book page (books with bound two-sided pages were a relatively new technology at the time, with many people still using scrolls). The fragment dates from less than a century after the gospel of John was written (and possibly just a few decades), thus helping in dating that work. There is no indication of any textual difference from later manuscripts – even the text on the missing parts of the front page seems of the right amount. The only exception is in the second line of the reverse side – there’s not quite enough room for the expected wording, and it seems likely that the duplicated words ΕΙΣ ΤΟΥΤΟ were not present.

In English, the passage reads:

… the Jews, “It is not lawful for us to put anyone to death.” This was to fulfil the word that Jesus had spoken to show by what kind of death he was going to die. So Pilate entered the Praetorium again and called Jesus and said to him, “Are you the King of the Jews?” …
… I am a king. For this purpose I was born and for this purpose I have come into the world – to bear witness to the truth. Everyone who is of the truth listens to my voice.” Pilate said to him, “What is truth?” After he had said this, he went back outside to the Jews and told them, “I find no guilt in him.”


Papyrus P52 (front and back) in the John Rylands Library

7. The Akeptous inscription in the Megiddo church, c. 250 AD

The Akeptous inscription is one of a number of inscriptions found in the mosaic floor of a 3rd century church which was discovered in 2005 while digging inside the Megiddo Prison in Israel (the date is just slightly later than the Dura-Europos church in Syria). The Akeptous inscription reads:

ΠΡΟϹΗΝΙΚΕΝ
ΑΚΕΠΤΟΥϹ,
Η ΦΙΛΟΘΕΟϹ,
ΤΗΝ ΤΡΑΠΕ-
ZΑΝ {Θω} {ΙΥ} {Χω}
ΜΝΗΜΟϹΥΝΟΝ

Phonetically:

Prosēniken Akeptous, ‘ē philotheos, tēn trapezan Th(e)ō Ι(ēso)u Ch(rist)ō mnēmosunon.

In English translation:

A gift of Akeptous, she who loves God, this table is for God Jesus Christ, a memorial.

Brief as it is, the inscription has several interesting features. First, Jesus Christ is being explicitly referred to as God, which tells us something about Christian beliefs of the time. Second, the inscription uses nomina sacra – divine names (“God,” “Jesus,” and “Christ”) are abbreviated with first and last letter, plus an overbar (this is denoted by curly brackets in the Greek text above). Third, the inscription records the gift of a prominent (presumably wealthy) female church member (the feminine definite article shows that Akeptous was female). And fourth, the reference to the construction of a table suggests that there were architectural features in the church to support the celebration of Communion, which tells us something about liturgy.


The Akeptous inscription in the Megiddo church

8. The Codex Sinaiticus, c. 340 AD

Our final inscription is a portion of the Codex Sinaiticus, a 4thcentury manuscript of the Christian Bible, containing the earliest complete copy of the New Testament. This Bible is a century later than the Megiddo church, and two centuries after Papyrus P52. Unlike Papyrus P52, it is written on vellum made from animal skins, and is written in beautiful calligraphic script. I have selected the passage John 1:1–3a:

ΕΝ ΑΡΧΗ ΗΝ Ο ΛΟΓΟϹ,
ΚΑΙ Ο ΛΟΓΟϹ ΗΝ
ΠΡΟϹ ΤΟΝ {ΘΝ}, ΚΑΙ
{ΘϹ} ΗΝ Ο ΛΟΓΟϹ. ΟΥ-
ΤΟϹ ΗΝ ΕΝ ΑΡΧΗ
ΠΡΟϹ ΤΟΝ {ΘΝ}. ΠΑ[Ν]-
ΤΑ ΔΙ ΑΥΤΟΥ ΕΓΕΝΕ-
ΤΟ, ΚΑΙ ΧΩΡΙϹ ΑΥΤΟΥ
ΕΓΕΝΕΤΟ ΟΥΔΕΝ

In English:

In the beginning was the Logos, and the Logos was with God, and the Logos was God. He was in the beginning with God. All things through him were made, and apart from him was not one thing made …

In the Greek, nomina sacra for “God” can be seen, together with a number of corrections (including, on the last line, an expansion of the contraction ΟΥΔΕΝ = “nothing” to ΟΥΔΕ ΕΝ = “not one thing”). Spaces between words had still not been invented, nor had punctuation or lowercase letters, which means that it is almost impossible to make sense of the text unless it is read aloud (or at least subvocalised). Fortunately, things have changed in the last seventeen centuries!


John 1:1–3a in the Codex Sinaiticus


Cities in Flight by James Blish: a book review


Cities in Flight by James Blish (1955–1962)

I recently re-read the science fiction classic Cities in Flight by James Blish. The galaxy-wide sweep of this four-part novel had stuck with me ever since I first read it as a child – likewise the role of the city that has two names twice. However, I had forgotten that the story opens in what is now our present (2019, with a prelude set in 2013 and a brief reference to an event of 2018). It was interesting to compare Blish’s vision of the future with our reality – where are our planetary outposts, for example? On the other hand, we have already begun forgetting facts, and letting computers remember them for us. Likewise, we have already started automating all “ordinary” jobs.

As an aside, it should be noted that the fourth part of the story, A Clash of Cymbals, was published in the U.S. as the less poetic The Triumph of Time.

The basic premise of this four-part novel is that a newly invented antigravity spacedrive allows cities to lift off into the galaxy and become “Okies” or itinerant labourers. Depressed American steel towns, for example, take off in search of planets with ore that needs refining. People, however, are still people, and not all the cities are friendly.

The writing is classic “hard SF.” There are even differential equations! The plot is heavily influenced by Oswald Spengler and the overall view of humanity is rather pessimistic (though not as pessimistic as some other novels). The second of the four parts, A Life for the Stars, focuses on a teenager (unwillingly) joining the exodus of cities, and thus has the form of a “coming of age” novel. The fourth part, like Poul Anderson’s Tau Zero and some other classic “hard SF,” ends with a sort of Big Crunch/Big Bang (although, as usual, the philosophical implications of a cyclic universe are inadequately explored).

The timeline of the novel spans more than two millennia:

  • 2018: Jovian expedition (in progress as They Shall Have Stars begins)
  • 2019–2021: development of the “spindizzy” antigravity spacedrive and first interstellar expedition (They Shall Have Stars)
  • 2105: fall of the West; earth ruled by Stalinist “Bureaucratic State” (hinted at in They Shall Have Stars)
  • 2310: the Battle of Altair begins the Vegan War, which in turn leads to the formation of the Hruntan Empire
  • 2375: rediscovery of the “spindizzy” on Earth; “Okie” cities begin to spread across the galaxy
  • 2522: collapse of the “Bureaucratic State” on Earth
  • 3111: New York, N.Y. leaves planet Earth (its career in space forms the major part of the novel)
  • 3602: Earth police take action against the remains of the Hruntan Empire (Earthman Come Home)
  • 3975: the Battle of Earth (Earthman Come Home)
  • 4104: the End (A Clash of Cymbals / The Triumph of Time)

As a classic, this novel is well worth a read, in spite of some writing flaws that are obvious on a re-reading. See here for a more detailed review and plot summary. Goodreads rates the combined novel as 3.95 stars, which is consistent with my 3.5 (I have a tougher scale).


Cities in Flight by James Blish: 3½ stars


Origin by Dan Brown: a book review


Origin by Dan Brown (2017)

I recently read Origin, the latest Dan Brown novel. Just about every Dan Brown novel covers topics dear to my heart, such as cryptography, computer simulation, the theory of computation, and artificial intelligence – but also the history of science, the history of Christianity, Dante, and Galileo. Dan Brown routinely promises an accurate depiction of these background topics (in this latest novel, he says “All art, architecture, locations, science, and religious organizations in this novel are real”). However (as I also pointed out for his Angels & Demons), the reality of his novels doesn’t quite live up to this claim. To pick just three examples, Yves Klein did not invent the pigment in International Klein Blue; “Pope Innocent XIV” was an Argentinian antipope, not a Spanish one; and it is not suprising when computer simulations produce results reflecting the assumptions built into their design.


Gaudí’s la Sagrada Família (image credit) plays a major part in the novel. It has been on my bucket list for decades. It still is.

Even as a work of pure fiction, Origin still disappoints. As with Dan Brown’s previous novels, the constant appearance of crazed gunmen doesn’t make up for the plot weaknesses. And a major theme of the novel is artificial intelligence – now, I don’t object to this being portrayed far in advance of current technology (that’s not uncommon in fiction), but the theme of artificial intelligence has been handled far better by (among others) Robert A. Heinlein, Arthur C. Clarke/Stanley Kubrick, Michael Crichton, and Peter F. Hamilton. I also found the book’s ending profoundly anticlimactic. However, if you’re a fan of Dan Brown novels, you’ll probably like this one too.

For other reviews, see The Week (“Dan Brown is a very bad writer”), The National (“The idea that a computer simulation would fundamentally destroy the faith of billions in their religions is so utterly, cluelessly juvenile that it seems right at home in a Brown novel”), and The Stream (“It’s sci-fi done by someone who knows nothing about sci-fi”).


Origin by Dan Brown: 2 stars


The Crucible of Time: a book review


The Crucible of Time by John Brunner (1983)

I recently re-read The Crucible of Time by science fiction author John Brunner (1934–1995). It is one of the last great triumphant-rise-of-human-progress novels where, in spite of all kinds of natural disasters, the inhabitants of a planet drag themselves through thousands of years of scientific development in order to escape their doomed planet (around the 80’s, science fiction became darker and more dystopian, as indeed, many of Brunner’s other novels are). What makes this novel stand out from a rather dull subgenre is that the characters are not human at all, but are some kind of mollusc. When you can get your readers to identify emotionally with a sort of intelligent slug or squid, then you’ve got serious writing talent: “‘But – !’ She sank back, at a loss. For the first time it was possible to see how pretty she was, her torso sleek and sturdy, her claws and mandibles as delicate as a flyet’s. Her maw still crowded, she went on, ‘But I always thought you and Professor Wam were enemies! When I heard you were giving a lecture and she had agreed to reply to you, I couldn’t really believe it, but I decided I had to be present, because you’re both on the other side from my parents. They are crazy, aren’t they? Please tell me they’re crazy! And then explain how you two can be acting like friends right here and now! I mean,’ she concluded beseechingly, ‘you don’t smell like enemies to each other!’

At one level, The Crucible of Time is a strange tirade against religion, having set up a universe in which the religious leaders are, by construction, dangerously wrong. This gives Brunner’s characters some more immediate opponents than the impending disaster itself, but these opponents seem a little too much like cardboard cut-outs most of the time. I was left somewhat confused as to why the universe of the novel contained religion at all. An evolutionary argument was implied, but it didn’t seem to make sense.

The novel (or rather, collection of linked stories) does have some fascinating descriptions of a civilisation that’s built mostly, but not entirely, on biology – in contrast to ours, which is built mostly, but not entirely, on physics. Brunner avoids tedious descriptions by giving animals names that suggest English equivalents. The alien equivalent of a domesticated camel is a drom, for example. The large domesticated water-creatures that perform the function of ships are barqs, briqs, and junqs: “‘Correct! Well, if a mindless plant can find a way to spread beyond its isolated patch, why shouldn’t we? Did it ever strike you that there must have been a first person who pithed a barq or briq, just as there was certainly a first who tamed a junq? Then, folk were confined to continents or islands, and had to trudge wearily from place to place unless they had a drom—and someone, equally, must have been first to ride a drom!’

In a similar vein are words like laq, sourgas, and stumpium (named after the planet Stumpalong). Checking Internet reviews, this aspect of the novel seems to be both loved and hated.

But I consider this novel to be one of the great science fiction classics; it’s well worth a read. See here for a more detailed review and plot summary.


The Crucible of Time by John Brunner: 3½ stars


Superman is boring

Superman, as orginally described, was invulnerable. Having a hero with superpowers that are too strong makes for a boring story, because a good story needs conflict. There are several ways of handling that, of course.

1. Kryptonite weakens my powers

According to some accounts, kryptonite was invented specifically to make Superman less invulnerable and boring (Paul Fairchild explains why this was a bad decision). Kryptonite, of one kind or another, is a classic solution to the problem of an overly strong superhero which, to some extent, has been used by multiple authors. It can be overused, however. If your superhero is always weak, why have such a character at all? A better variation of this approach is for the protagonist to carry his or her own metaphorical kryptonite inside, as some kind of “fatal flaw.”

2. My powers come at a heavy cost

This is one of the easiest ways for an author to ensure that his or her character does not overuse their superpowers. These superpowers may cause pain, coma, physical harm, or other damage that enforces a break between uses of the superpowers. For example, the psychic Greg Mandel in Peter F. Hamilton’s Mindstar Rising and its two sequels suffers severe headaches when his powers are used to excess. Variations of this approach are used in a number of fantasy novels.

3. My powers disturb or frighten me

A good example of this option is Doctor Who, in the eponymous TV series, who often needs to be talked into taking action. The advantage of this approach is that it produces a great deal of interesting dialogue on why the superpowers are disturbing or frightening.

4. I am still learning to use my powers

This option is particularly common in young adult fiction. It allows the author to have an attempted use of powers either succeed or fail at any point; but this makes sense with a young protagonist. The young magician Pug in Raymond E. Feist’s Riftwar Saga is a good example. So is Luke Skywalker in the original Star Wars movie trilogy. To some extent, Aragorn in The Lord of the Rings can be viewed as having a combination of (3) and (4). But, however the author does it, I think that some limitation on superpowers is essential for a story to remain interesting. What do you think?


The Invention of Clouds: a book review


The Invention of Clouds: How an Amateur Meteorologist Forged the Language of the Skies by Richard Hamblyn (2001)

I recently read The Invention of Clouds by Richard Hamblyn, who also wrote Terra (which I reviewed some years ago). The present volume focuses on the Quaker pharmacist Luke Howard, who produced a taxonomy of clouds in 1802. Essentially the same classification is still used today (but not, as Hamblyn points out, without considerable debate during the 1800s):

Although the focus is on Howard’s work and life, Hamblyn in fact provides a brief history of meteorology (or at least of the study of clouds), and there is a chapter on the Beaufort scale. Contemporary literature referred to includes:


Google Ngrams plot for three of the cloud types (with and without hyphens). The words “cirrostratus” and “cirrocumulus” first appear in reprintings of Howard’s pioneering essay, while the word “cumulonimbus” is introduced around 1887. There is a renewed spike of interest in cloud types beginning in the early 1940’s.

The Invention of Clouds also has some interesting comments on clouds in art and on how to get an education at a time when the two English universities banned non-Anglicans from attending. However, the book does have a few small errors. For example, cloud droplets are not “a mere millionth of a millimetre across,” but in the range 0.005 to 0.05 mm. However, that does not stop the book from being both enjoyable and informative (although I did wish for colour images). See also this review from the NY Times.


The Invention of Clouds by Richard Hamblyn: 3½ stars