John Stevens Henslow, a guiding light for his student Charles Darwin


John Stevens Henslow (6 February 1796 – 16 May 1861) was an English clergyman, botanist and geologist.

Henslow first came to Cambridge to study mathematics but it was his geological work in field studies of the Isle of Man and Anglesey that brought him fame. By the age of 27 he was elected Professor of Mineralogy and two years later became Professor of Botany at the University of Cambridge, a post he was to hold until his death in 1861. Henslow’s research focused on the nature of species and between 1821 and 1835 he compiled a Herbarium of 3,654 sheets containing specimens from over 10,000 plants. He was renowned for his new teaching techniques. He used his own illustrations in lectures, introduced practical science classes, and led walks around the Cambridge district as he taught natural history. He fostered independent discovery and utilized unusual field trips for his students.

In order to persuade farmers to apply scientific methods to their operations, Henslow gave public lectures on the fermentation of manure and wrote newsletters for publication in local newspapers. During the potato famine (1845-46) in Ireland, he showed stricken farmers how to extract starch from rotten potatoes. In 1837, Henslow accepted the rectorship of the neglected parish of Hitcham in Suffolk, where we was to remain for the rest of his life.

And he mentored Charles Darwin and recommended him to Captain FitzRoy as aspiring scientist on the HMS Beagle voyage.

Henslow received numerous letters and botanical specimens from Darwin and published part of  Darwin’s scientific findings. Henslow thus helped establish Darwin’s reputation as a botanist, geologist and fossil collector.

Their friendship was lifelong. In 1859, Charles Darwin published his Origin of Species and send a copy to Henslow, his “dear old master in natural history” acknowledging that “ I fear, however, that you will not approve of your pupil in this case.” – And he was right:  Henslow did not share Darwin’s view on the evolutionary history of living beings via natural selection, as he said in a letter to  Joseph Dalton Hooker in May 1860:

“I do not disguise my own opinion that Darwin has pressed his hypothesis too far—but at the same time I assert my belief that his Book is […] the ‘Book of the Day’”

Henslow did defend, though, his former pupil:

“I stuck up for Darwin as well as I could, refusing to allow that he was guided by any but truthful motives, and declaring that he himself believed he was exalting & not debasing our views of a Creator, in attributing to him a power of imposing laws on the Organic World by which to do his work, as effectually as his laws imposed upon the inorganic had done it in the Mineral Kingdom” 

Henslow died on 16 May 1861, just two years after the Origin of Species had been published. In a contribution to a biography of Henslow, Charles Darwin describes his friendship with him in the following words:

“I have not as yet mentioned a circumstance which influenced my whole career more than any other. This was my friendship with Professor Henslow. Before coming up to Cambridge, I had heard of him from my brother as a man who knew every branch of science, and I was accordingly prepared to reverence him. He kept open house once every week when all undergraduates, and some older members of the University, who were attached to science, used to meet in the evening. I soon got, through Fox, an invitation, and went there regularly. Before long I became well acquainted with Henslow, and during the latter half of my time at Cambridge took long walks with him on most days; so that I was called by some of the dons “the man who walks with Henslow;” and in the evening I was very often asked to join his family dinner. His knowledge was great in botany, entomology, chemistry, mineralogy, and geology. His strongest taste was to draw conclusions from long-continued minute observations. His judgment was excellent, and his whole mind well balanced; but I do not suppose that any one would say that he possessed much original genius. He was deeply religious, and so orthodox that he told me one day he should be grieved if a single word of the Thirty-nine Articles were altered. His moral qualities were in every way admirable. He was free from every tinge of vanity or other petty feeling; and I never saw a man who thought so little about himself or his own concerns. His temper was imperturbably good, with the most winning and courteous manners; yet, as I have seen, he could be roused by any bad action to the warmest indignation and prompt action.”


  • John Stevens Henslow, in the public domain
  • Photo taken in September 2015, at the Adam Sedgwick Museum in Cambridge
  • Commemorative plaque at the entrance to the Botanic Garden in Cambridge


Earth Day: Caring for our common home


22 April is Earth Day. The first was celebrated in 1970 at the beginning of the modern environmental movement.

The early roots date back to the 19th century: J. Sterling Morton was a Nebraska pioneer, a writer and editor for Nebraska’s first newspaper, and later secretary of the Nebraska Territory. He advocated planting trees in what was then a dusty and treeless prairie. At a meeting of the State Board of Agriculture in January 1872, Morton proposed that Nebraska citizens set aside April 10 as a day to plant trees. He suggested offering prizes as incentives for communities and organizations that planted the most trees. It’s said that Nebraskans planted about one million trees on that first Arbor Day in 1872. Ten years later, in 1882, Nebraska declared Arbor Day as a legal holiday and the date was changed to Morton’s birthday, April 22.

Though Earth Day may now be synonymous with small-scale tree planting and volunteer cleanup projects, the first Earth Day actually had its sights set on bigger political projects. Earth Day demonstrations created public support for the creation of the Environmental Protection Agency, authorized by Congress in December 1970. Earth Day also contributed to the passage of the Clean Water, Clean Air and Endangered Species acts.

Giovanni Battista Riccioli – Scientific Integrity


Giovanni Battista Riccioli (17 April 1598 – 25 June 1671) was an Italian astronomer and geographer. At the age of sixteen, he entered the Jesuit order. He taught literature, philosophy and theology, first in Parma and then Bologna. Considered one of the primary astronomers of the 17th century, he wrote the important work Geographia et Hydrographia reformata (1661) in twelve books. He is known, among other things, for his experiments with pendulums and with falling bodies, for his discussion of 126 arguments concerning the motion of the Earth, and for introducing the current scheme of lunar nomenclature.

Prof. Chris M. Graney says: “Riccioli set a fine example for all the free-fall experiments that would follow. He was thorough. He provided an extensive description of his experimental procedure. He gathered data of sufficient quality to assess accurately the model in question.

But Riccioli’s work is also a standard of scientific integrity: He had set out expecting to disprove Galileo, but even when his experiments vindicated Galileo, he made a point of promptly sharing the news with an interested colleague. His attitude, like his experiment, was that of a fine scientist.”


Picture: Riccioli as portrayed in the 1742 Atlas Coelestis (plate 3) of Johann Gabriel Doppelmayer (wikipedia)

Christopher M. Graney, Anatomy of a fall: Giovanni Battista Riccioli and the story of g, Physics Today 2012

The coronavirus: Is there good in natural evil? – Useful Resources on COVID-19 (II)


“How can all-good God allow natural evil?” is asked anew whenever a big catastrophe occurs, like the tsunami in 2004, the earthquake in Haiti in 2010, and now with the COVID-19 crisis. There are no easy answers. And here is not an elaborated essay, but rather a collection of thoughts from Christian scholars and leaders, most of them voiced in our current situation.  

We may approach this question from three different angles:

1.           Viruses are part of God’s creation and all creation is good. Therefore, viruses are good, and so is the coronavirus.

In Genesis 1, we read several times: “And God saw that it was good.” The claim that the coronavirus is good, is a difficult claim – at least to me. Still, it has merits. The Orthodox theologian Cyril Hovorun explains:

“Per se, this virus, as any micro- or macro-organism, is a part of God’s creation. As a physical reality and a part of nature, the virus is ontologically “good”, like any creature (see Gen 1:21). We consider floods, volcanoes, typhoons to be evil, but they are natural processes, and as such are not ontologically evil. The snakes and spiders that bite us are also deadly to us, but by their nature they are good.

Together with other viruses, bacteria, and other microorganisms, the COVID-19 is part of the ecosystems created by God. I will not now go into the question whether these ecosystems have been created directly by God or emerged through the laws of evolution laid down by God. I’ll just say that some parts of these ecosystems are helpful for us, and some are not. However, regardless of this, they are all a part of God’s creation. Moreover, COVID-19, together with other creatures, is included in the “recapitulation” described by Paul in the Ephesians: “To unite (ἀνακεφαλαιώσασθαι) all things in Him, things in heaven and things on earth” (1:10).” [1]

And P. Nicanor Austriaco, a Catholic priest in the Dominican Order and a biologist, reminds us:

“God makes each living thing so that it can give glory to Him. A virus gives glory to God in the same way that sharks and cobras give glory to God. They simply reveal the ingenuity and creativity of God who creates all of them. In being sharks, cobras, and viruses, they are already good. Notice that we understand that sharks and cobras are good, even when they kill humans. They kill humans because that is what sharks and cobras do when they encounter humans that threaten their well-being. […] For animals and some plants, to survive means that others have to die. This is the rhythm of life. Antelopes die so lions may live. Squirrels die so eagles may live. Insects die so Venus fly traps may live. So in the living world, every organism is destructive.

For COVID-19, some of us die so it may live. Notice that not all die. In fact, 98% of COVID patients survive. Therefore, you cannot say that the virus’s end is to kill humans. The virus infects humans in order to live. Tragically, some are too weak to sustain that infection and they die. But it is not the virus alone, but the virus and the weakened human body together that kill.” [2]

The book of Wisdom tells us  “For you love all things that exist, and detest none of the things that you have made; for you would not have made anything if you had hated it” (Wis 11:24)

2.           God created a world that is good, but still unfinished.

Good does not mean perfect. In Genesis 1, we are not told that God saw that it was perfect, but that it is good. Therefore, Daniel Harrell in the Christianity Today editorial of 17 March 2020 “Is the Coronavirus Evil? Or is this part of life in the world God made?” states: 

“Better to view creation not as something perfect gone awry, but as something begun as very good only not yet finished.” [3]

And in “Laudato Sí” (2015), the encyclical on the care of our common home, the earth, Pope Francis said:

“Creating a world in need of development, God in some way sought to limit himself in such a way that many of the things we think of as evils, dangers or sources of suffering, are in reality part of the pains of childbirth which he uses to draw us into the act of cooperation with the Creator. God is intimately present to each being, without impinging on the autonomy of his creature, and this gives rise to the rightful autonomy of earthly affairs. His divine presence, which ensures the subsistence and growth of each being, ‘continues the work of creation.’ The Spirit of God has filled the universe with possibilities and therefore, from the very heart of things, something new can always emerge: “Nature is nothing other than a certain kind of art, namely God’s art, impressed upon things, whereby those things are moved to a determinate end. It is as if a shipbuilder were able to give timbers the wherewithal to move themselves to take the form of a ship.” [4]

Interestingly, the philosopher Gottfried Wilhelm Leibniz claimed in his “Theodicy”, that the actual world is the best of all possible worlds. Thomas Aquinas – who was deeply convinced of the goodness of all creatures – answered differently: God could have created a better universe – it would have been different. But it would not have been a universe without pain and suffering. [5]

3. The Question “Why”

 In his article “Christianity Offers No Answers About the Coronavirus. It’s Not Supposed To,” N. T. Wright, Professor of New Testament and Early Christianity at the University of St Andrews says:

“Rationalists (including Christian rationalists) want explanations; Romantics (including Christian romantics) want to be given a sigh of relief. But perhaps what we need more than either is to recover the biblical tradition of ‘lament‘. Lament is what happens when people ask, “Why?” and don’t get an answer.” [6]

Lament has rich biblical sources, one of them is in Psalm 22 and contains the word Our Lord said on the Cross: “My God, my God, why hast thou forsaken me?“. Lament may only only accompany us in these days of Holy Week, but may also lead us further in our personal prayer, as the German theologian Romano Guardini beautifully explains:

“The spirit gives the answer to those questions to which there is no answer because they contain the word “why” together with the word “I”. “Why do I have to bear this suffering? Why am I denied what others have? Why do I have to be the way I am?” These are the really important questions, and people like books remain silent on them. The answer to them only comes when the inside becomes free of bitterness and rebellion. My own will must be in agreement with reality by recognizing God’s will in my life, not only by reason, but with the heart. Something in my innermost must be instructed and give consent; only then does that “Why?” receive an answer and there will be peace through truth. That is what the Holy Spirit does.” [7]

For some, the worst in the current situation is the pain of having lost a beloved to the pandemic, others may fear sickness and misery; some may feel in an overcrowded place due to the “stay home” orders, or reversely, others may face loneliness. Some people may be overwhelmed by the workload, and others may be utterly bored. Only in prayer, we may understand the current situation and our own situation. In our lamentful prayer, we will get a personal answer helping us to respond in the best  way to this challenge, and to better understand God’s grace in store for us.


 [1] Cyril Hovorun, COVID-19 and Christian (?) Dualism, in: Public Orthodoxy, 23 March 2020

[2] Austriaco Nicanor, on facebook, 21 March 2020

[3] Daniel Harrell, Is the Coronavirus Evil? Or is this part of life in the world God made?, Christianity Today, 17 March 2020

[4] Pope Francis, ‘Laudato Si’, 2015, no 80

[5] see blog post: Aquinas on the best of all possible worlds, 26 March 2016

[6] N.T.Wright, Christianity Offers No Answers About the Coronavirus. It’s Not Supposed To, Time, 29 March 2020

[7] Romano Guardini, Die Vorschule des Betens. Translation mine.
‚Der Geist gibt die Antwort auf jene Fragen, auf die es keine Antwort gibt, weil in ihnen das Wort “warum” zusammen mit dem Wort “ich” vorkommt. “Warum muss ich dieses Leid tragen? Warum ist mir versagt, was andere haben? Warum muss ich so sein, wie ich bin?” Das sind die eigentlichen Fragen, und auf sie bleiben Menschen wie Bücher stumm. Die Antwort auf sie kommt nur, wenn das Innere von Bitterkeit und Auflehnung frei wird. Mein Lebenswille muss ins Einverständnis kommen mit dem, was ist, indem ich darin den Willen Gottes erkenne; das aber nicht nur mit dem Verstnd, sondern mit dem Herzen. Etwas in meinem innersten muss belehrt werden und sich einverstanden geben; dann erst bekommt jenes “Warum?” eine Antwort, und es wird Frieden durch die Wahrheit. Das wirkt der Heilige Geist.‘

Useful Resources on COVID-19 (I)


The new Corona crisis is the first pandemic that we experience everywhere, in every continent, in every community. Much has been said and shared already on fb and twitter, but here will be all in one place.

Frodo: “I wish it need not have happened in my time.”

Gandalf: “So do I, and so do all who live to see such times. But that is not for them to decide. All we have to decide is what to do with the time that is given us.”

J.R.R. Tolkien, “The Fellowship of the Ring”

The coronavirus nCoV-2:

Viruses are in itself pretty helpless. Every bacterium, every single-cell organism is much better off, they can actively find their sources of energy (being it light or food), and move into better environments. Viruses lack this faculty of sensing, and they lack metabolism – therefore the question whether viruses are alive can be answered with yes or no, depending on what we consider essential for “living beings”. Nonetheless, viruses can do big harm to us, if they find ways to get into the cells of our body where they take over the control over the control of the cells that start producing new viruses en masse. 

Coronaviruses have RNA as genomic information. The name “coronavirus” is derived from Latin corona, meaning “crown” or “wreath”, itself a borrowing from Greek κορώνη korṓnē, “garland, wreath”. The name refers to the characteristic appearance of virions (the infective form of the virus) by electron microscopy, which have a fringe of large, bulbous surface projections creating an image reminiscent of a crown or of a solar corona.

For a good general introduction, read this article on Wikipedia .

The most important measures to combat the spread of this epidemic:

  • Wash your hands frequently because soap disrupts the lipid envelope of the virus
  • Maintain Social Distancing – Dr. Sy Garte, biologist and believer in Christ, explains in eight minutes why social distancing is so important. He says: “With school and church closures, cancellations of so many public events, working from home, some people are asking if this is a panic reaction. No, it isn’t. I have just uploaded a video showing why it’s necessary to practice social distancing NOW, even if not a single case of Covid 19 has appeared in your community. Please watch and spread the word.”
  • Avoid touching eyes, nose and mouth
  • Practice respiratory hygiene: Droplets spread virus. By following good respiratory hygiene – covering your mouth and nose with your bent elbow or tissue when you cough or sneeze -, you protect the people around you from viruses such as cold, flu and COVID-19.
  • If you have fever, cough and difficulty breathing, seek medical care early
  • Follow all instructions from your national and local Authorities

These instruction were taken from the WHO website.

We need to flatten the curve

This article in the NYT explains why slowing the spread of the infection is nearly as important as stopping it:

NIH Director Francis Collins

“There are estimates that if nothing goes right and if we fail to flatten the curve and if health systems are overwhelmed, we might see the deaths of as many as a million and a half people in the United States”, says Dr. Francis Collins, director of the NIH and founder of Biologos, in an interview in which he not only takes a thorough review into the Covid-19 pandemic, but also delves into his deep faith, and his friendship with Christopher Hitchens. On his Blog, he has a post explaining that a recent genomic studies points to a natural origin of COVID-19: Do not listen to rumors, is an important advice.

Interactive Graphics:

Development of cases, worldwide and per country, from the John Hopkins University

In response to this ongoing public health emergency, we developed an interactive web-based dashboard hosted by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University, to visualize and track reported cases in real-time. The dashboard, first shared publicly on January 22, illustrates the location and number of confirmed COVID-19 cases, deaths and recoveries for all affected countries.

Mapping 2019-nCOV

nCoV-2, Mutational Changes over time

This phylogeny shows evolutionary relationships of hCoV-19 (or SARS-CoV-2) viruses from the ongoing novel coronavirus COVID-19 pandemic. This phylogeny shows an initial emergence in Wuhan, China, in Nov-Dec 2019 followed by sustained human-to-human transmission leading to sampled infections. Although the genetic relationships among sampled viruses are quite clear, there is considerable uncertainty surrounding estimates of transmission dates and in reconstruction of geographic spread. Please be aware that specific inferred transmission patterns are only a hypothesis.

Also these 10 women scientists didn’t see a conflict between science and faith


Today is Women’s day – time to remember the contribution of Christian female scientists and time to post the 2nd installment (first one here), bringing the number of women scientists portrayed on our blog to 30. We cover women from 4 centuries, contributing to mathematics, chemistry, astronomy, geology and scientific illustration.

Elena Cornaro Piscopia (1646-1684) was the first woman to receive a ‘Doctor of Philosophy’, a ‘Ph.D.’ degree in 1678. Although she was learned in mathematics and other science fields, her real focus was in theology and philosophy. The Roman Catholic Church, though, did not think at that time it was proper for a woman to earn a degree in theology. The University of Padua allowed Piscopia to graduate with her Ph.D. in Philosophy instead.  Ceremonies of the sort were usually held in one of the University’s buildings, but there were so many people who wanted to come watch the proceedings that they could not all fit into University Hall, and thus they chose a larger place to hold the ceremony. It was especially remarkable when we consider that the University of Padua did not award another Ph.D. to a woman for over 300 years. Elena was a member of various academies and was esteemed highly throughout Europe. In 1665, she took the habit of a Benedictine Oblate and devoted the last seven years of her life to charity and working with the poor. She died at the age of 38 of tuberculosis.

Marie-Anne Lavoisier (1758-1836) was a French chemist and noble. Madame Lavoisier was the wife of the chemist and nobleman Antoine Lavoisier and acted as his laboratory companion and contributed to his work. Her husband, Antoinette Lavoisier, was sentenced to death in the aftermath of the French Revolution, after having found again his faith in God. She herself was a faithful Catholic and was theologically well versed. She was instrumental in the 1789 publication of her husband’s Elementary Treatise on Chemistry, which presented a unified view of chemistry as a field. She contributed thirteen drawings that showed all the laboratory instrumentation and equipment used by the Lavoisiers in their experiments. She also kept strict records of the procedures followed, lending validity to the findings Lavoisier published.

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Georg Cantor and infinity


On 03 March 1845, the German mathematician Georg Cantor was born in St. Petersburg. In 1862, he entered the Federal Polytechnic Institute in Zurich, eventually becoming a member of the mathematics department. At the death of his father, he left Zurich for Berlin where, in addition to his mathematical interests, he began to study philosophy and theology, two disciplines he would pursue for the rest of his life. He is considered one of the founders of set theory.

He is also credited with systemizing various notions of infinity, differentiated as:
a) that which is potentially infinite, undetermined, and capable of incremental increase;
b) transfinite or relative actual infinity, determined, and capable of incremental increase; and
c) absolute actual infinity, determined, and incapable of incremental increase.

He noted that this last notion of infinity does not belong to mathematics but rather can only be predicated of a notion of God within the metaphysical realm.