Where did our sense of curiosity come from?

The pump of curiosity in I-M

My recent article for I-M on solar eclipses and the Fermi paradox is now available online.

As Daniel C Dennett, a philosopher and cognitive scientist, has observed, searching for explanations is a central feature of our species. Where does our sense of curiosity come from? As an exercise in fun speculation, I propose it could have been influenced by two rare-earth factors.

The (extremely tentative) idea is that solar eclipses may have acted as a ‘pump of curiosity’ for early humans.

We can safely say that eclipses are not rare in the universe. But the perfect solar eclipses we experience on earth, where the moon and sun combine in spectacular fashion every couple of centuries or so, may be exceptionally rare. Even if these eclipses are one among many factors that led to the development of curiosity, it means that a key human trait is partly a consequence of two things that are nothing more than coincidences: the ratio of the moon’s and the sun’s diameters is the same as the ratio of their distances, and the moon’s orbit is tilted.


I’m currently working on a paper about the pump of curiosity, which I’m hoping to present at the International Astronomical Union Symposium 367 later this year. As part of my research, I’m grateful to a number of people who have generously shared their knowledge and expertise with me, including Cecilia Lazzoni, who might have found our first exomoon; Tetsuro Matsuzawa, who studies chimpanzees and the evolutionary origins of human behaviour; and Jay Pasachoff, author of many fascinating papers and books on how eclipses and astronomy have inspired human culture.

The dog days of summer

The hottest days of summer are known as the dog days. There’s a fun bit of astronomy behind this expression: it’s the time of year when Sirius — also known as the dog star — rises just before the sun.

The August pre-dawn sky, with Sirius rising in the east just ahead of the sun. In 2020, Venus is also getting in on the act…
(Night Sky Map from timeanddate.com)

The dog star, which faithfully follows the hunter Orion across the sky, is easily our brightest star. It’s so bright, in fact, that the ancient Greeks believed it added to the heat of summer by rising at the same time as the sun. Hence, the dog days of summer.

The pump of curiosity

The summer 2020 issue of I-M Intelligent Magazine

I-M Summer 2020 cover

… includes “an exercise in fun speculation” by me on a potential link between solar eclipses and the Fermi paradox.

I-M VolXIII The pump of curiosity

According to the Copernican principle, there is nothing special about the earth’s place in the universe. Except for the awkward fact that — on current evidence — it’s the only place in the universe to have produced an intelligent and curious species capable of reaching beyond its home planet. In the words of the revered physicist Enrico Fermi: where is everybody?

One solution to the paradox is the rare earth hypothesis. This proposes that the development of complex life on our planet depended upon a labyrinthine set of circumstances that may be vanishingly rare within the universe. By chance, everything about the earth is perfectly balanced in terms of physics (eg, its stable orbit), chemistry (eg, its abundance of metals) and biology (eg, the development of photosynthesis).

In my article for I-M, I’ve taken the rare earth hypothesis one step further:

Does the earth have some unique ingredient that enabled not only the development of complex life, but also the development of intelligent and curious life? After all, it is not biological complexity per se that has led to humans reaching beyond our home planet, or pondering questions such as “where is everybody?”

We live in a world of routine processes: sunrises and sunsets, tides and seasons, predators and prey. (Even earthquakes and volcanoes are routine events in many parts of the world.) But, as the philosopher and cognitive scientist Daniel C Dennett points out, “too much regularity in the selective environment can be a trap.” In an environment where novelty remains below a certain threshold, brains may never receive the stimuli they require to develop human-like levels of curiosity.

A solar eclipse, on the other hand, is anything but routine. There is no warning or preamble; it comes — literally — out of a clear blue sky. Given that even modern-day observers can be overwhelmed by an eclipse, the sun’s sudden disappearance must have created an unparalleled cognitive crisis for our ancestors.

Could total and annular eclipses have acted as a pump of curiosity for early humans? Crucially, they occur at what might be an ideal frequency. If they occurred more frequently, they would have become routine events, and not provided sufficient novelty to stimulate the brain. If they occurred less frequently, they would not have provided enough stimuli to different communities, at different times, to kindle the first flames of human curiosity.

The frequency of solar eclipses — plus the scale of their impact on humans — depends upon two coincidences:

(1) The ratio of the moon’s and the sun’s diameters is the same as the ratio of their distances. This means that, although their actual sizes are two orders of magnitude different, the moon and the sun are the same size in our sky

(2) The moon’s orbit is tilted, which means the earth, moon and sun do not fall into alignment every month.

If such a combination of coincidences is rare within the cosmos, the pump of curiosity could be a solution to the Fermi paradox. Perhaps we are the only species in the universe to ask “where is everybody?”


Note: I’m grateful to Stephen Webb (the author of Where is everybody? Seventy-five solutions to the Fermi paradox and the problem of extraterrestrial life), John G Cramer (who proposed a Fermi paradox solution called the pump of evolution in the 1980s) and Daniel C Dennett (the above quote appeared in From bacteria to Bach and back: The evolution of minds) for their comments on a previous version of this article.

Cosmic inflation, 40 years on

“It is very natural for scientists to come up with the same idea at the same time. Researchers read articles from around the world and from this, new ideas are born.”

My latest piece for Physics World is an interview with Katsuhiko Sato. Forty years ago, Sato was one of a small number of physicists — working in different countries around the world — who independently came up with the theory of inflation. This is the idea that, just after the big bang, the universe went through a period of rapid, exponential growth.

“What surprised me regarding inflation theory is that today many scientists are still working on new types of inflation,” he says.

In our interview, Sato also talks about projects such as the International Linear Collider, an ambitious particle accelerator that could be built in the north of Japan.

Ephemeral moments with two planets, the moon, and the sun

A little ephemeral moment will play out over the evenings of 21 and 22 May: the two innermost planets — Mercury and Venus — will be close together on the western horizon.

Mercury and Venus, 21-22 May 2020Image: EarthSky

Venus (which, as you may have noticed, has been spectacularly bright recently) will come into view about 20 minutes after sunset; Mercury (which is always a bit challenging to see) should appear about half an hour later.

The evening show will continue into the weekend, when the two planets will be joined by a thin crescent moon.

Mercury, Venus and the moon: 23-24 May 2020Image: EarthSky

Looking ahead, in four weeks’ time — when the moon completes its lunar cycle — there will be another ephemeral moment. The new moon of 21 June will line up perfectly with the sun and produce an annular solar eclipse.

An annular eclipse occurs when the moon is too far from the earth (and, therefore, too small) to cover the sun completely. Instead, the sun appears as a dazzling ‘ring of fire’ around the moon (annular means ring-shaped).

Annularity will be visible along a narrow path — indicated by the VERY thin central line in the map below — that runs from central Africa to the western Pacific. A partial eclipse will be visible across other parts of Africa and Asia (indicated by the shaded areas below).

Annular eclipse map, 21 June 2020Image: timeanddate.com

Once again, I’ll be joining the team at timeanddate.com to provide live coverage of this event.

Time and Date livestream

Needless to say, things will be a bit different to our usual live coverage! The current restrictions on travel mean we’ve had to cancel our plan to send the timeanddate.com mobile observatory to Oman. (We’re also waiting to see what the effect of covid-19 will be on our coverage of the total solar eclipse on 14 December; we’re hoping to broadcast this live from Piedra del Águila, in the Patagonia region of Argentina.)


NEVER look at the sun with the naked eye. Even if the sun is 99% covered by the moon, the remaining sunlight is extremely bright and can cause permanent damage to the eye. (The only time it is safe to view a solar eclipse with the naked eye is during the few short minutes or seconds of totality during a total eclipse, when the sun is completely covered — never during a partial eclipse or annular eclipse.)

Can you solve this logical-thinking puzzle?

Picture of Saturn
Image: NASA/JPL/Space Science Institute

For anyone locked down and in need of some mental exercise, here’s a quick Japanese challenge. If you only speak English, the puzzle is impossible to solve. If, however, you speak Spanish — or one of a number of other languages, including French, Welsh or Hindi — it becomes an exercise in logical thinking. (The answer is at the bottom of this page, in a piece I wrote about the recent TESOL-SPAIN English-teaching convention at the University of Salamanca.)


In Japanese, the names of the five planets that can be seen with the naked eye are:

  • Mercury – suisei
  • Venus – kinsei
  • Mars – kasei
  • Jupiter – mokusei
  • Saturn – dosei

If the Japanese word for Tuesday is kayoubi, what is the word for Friday?

Is it (a) suiyoubi, (b) kinyoubi, (c) mokuyoubi, or (d) doyoubi?


The link between science and language
Graham Jones | TESOL-SPAIN newsletter (April 2020)

The theme of this year’s TESOL-SPAIN convention was “Breaking barriers”. As an English teacher with a background in astrophysics, my least favourite barrier within education is the one between science and the humanities. The two areas are more deeply intertwined than we often appreciate.

For instance, in his opening plenary in Salamanca, Lindsay Clandfield pointed out that our ideas about robots mostly come from science fiction (step forward C-3PO et al). Significantly, this is true even for scientists and engineers: “Many of the things that people in robotics and artificial intelligence do — they’re quite open about saying they are following things that they were obsessed with as younger people through science fiction,” noted Lindsay.

In the same spirit of “Breaking barriers”, before I began my Sunday-morning presentation in Salamanca, I did a warm-up “challenge” to highlight a link between astronomy and language. If you’d like to have a go, here it is…

In Japanese, the names of the five planets that can be seen with the naked eye are: Mercury – suisei; Venus – kinsei; Mars – kasei; Jupiter – mokusei; Saturn – dosei. If the Japanese word for Tuesday is kayoubi, what is the word for Friday? Is it (a) suiyoubi, (b) kinyoubi, (c) mokuyoubi, or (d) doyoubi?

If you only speak English, the puzzle is impossible to solve. If, however, you speak Spanish, it becomes an exercise in logical thinking. Tuesday (kayoubi) is related to Mars (kasei) in the same way that martes is related to Marte; from this we can deduce that Friday is kinyoubi (since viernes is related to Venus).

Answer = (b) kinyoubi

This can be an interesting topic to think about with students. English retains three clear connections between celestial bodies and days of the week: Satur(n)day, Sunday and Mo(o)nday. For the other days, the connections are still there, but they have been hidden beneath a layer of Germanic influence. For example, Tuesday comes from the Norse god Tiw, who is associated with Mars. Spanish, meanwhile, has lost two connections: sábado comes from the Sabbath (not Saturn), while domingo comes from Dominica (the Lord’s Day).

The deeper purpose of education

The 2020 Annual National Convention of TESOL-SPAIN took place last week at the University of Salamanca.


Image: Fernando Vázquez Yáñez/Creative Commons

My personal highlight was a talk on “Positive Language Education” by Sarah Mercer, head of English Language Teaching at the University of Graz in Austria. She began by posing two questions that formed part of a study led by Martin Seligman at the University of Pennsylvania:

  • In two words or less, what do you want for (your) children in life?
  • In two words or less, what do schools teach?

When Seligman’s team compared the answers they obtained to these questions, they found “there is almost no overlap between the two lists”. In Salamanca, Sarah followed this up with a quote from the British education researcher Guy Claxton:

“In the thrall to content and qualifications, we have forgotten the deeper purpose of education. In the rush to make young people into successful exam passers, we have overlooked their deeper need to become successful people…”

Overall, it was an exciting fit with the research we’re doing in Japan into personal goal-setting and, in particular, the idea of connecting language-learning goals with life goals. (Sarah kindly let me borrow a couple of her slides for my presentation the following day — so, thank you Sarah!)


Our research is supported by a grant from the Japanese government, reference number 18K00874.

Breaking barriers within education

Next month the University of Salamanca will host the TESOL-SPAIN 43rd Annual National Convention.

The theme of the convention — Breaking barriers: make it happen, make it matter! — “invites us to reflect on the powerful forces that contribute to modern life, including the emergence of Artificial Intelligence with its unforeseeable impact on our lives. Students must be prepared for the demands of this ‘brave new world’ by learning useful and relevant knowledge, skills, character qualities and learning strategies. However, we face many challenges as educators and the barriers to education are still many and varied and the perceived vulnerability of certain social groups requires timely solutions.”

The keynote speakers are Daniel Xerri (University of Malta), Judit Kormos (Lancaster University), Lindsay Clandfield and Sarah Mercer (University of Graz). I’ll be there, too, to share some findings from our research at the University of Shiga Prefecture into the CEFR language framework, and how it can help personal goal-setting.


Phnom Penh. Image: Chanrasmey Miech/Wikimedia Commons.

This weekend, meanwhile, my research partner Dr Maki Taniguchi will be at the 16th Annual CamTESOL Conference, at the Institute of Technology Cambodia in Phnom Penh. Maki’s talk is also based on our work in Japan: she will be discussing the benefits of ‘team teaching’ (ie, having two teachers for one class).


Our research is supported by a grant from the Japanese government, reference number 18K00874.