Category Archives: Science

Arts, Philosophy, Science

Philosophy: The Scientific Revolution

RENAISSANCE

Intro: Although the Renaissance was primarily an artistic and cultural movement, its emphasis on free thinking challenged the authority of religion, and paved the way for an unprecedented age of scientific discovery

Tradition undermined

THE Scientific Revolution began with the publication in 1543 of Nicolaus Copernicus’s De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), which presented evidence contradicting the notion of a geocentric universe. A description of this is given at the end of this article.

That same year, Andreas Vesalius published De humani corporis fabrica (On the Fabric of the Human Body), which overturned many orthodox ideas in anatomy and medicine. What followed was a profound change in the approach to enquiry into the natural world. Conventional wisdom, including the dogma of the Church, was no longer blindly accepted, but challenged. Even the work of Aristotle, who had initiated the idea of natural philosophy based on methodical observation, was subject to scientific scrutiny.

At the forefront of this scientific revolution were philosophers such as Francis Bacon, whose Novum Organum (New Instrument) proposed a new method for the study of natural philosophy – systematically gathering evidence through observation, from which the laws of nature could be inferred. But there was also a new class of thinkers and scientists, including Nicolaus Copernicus, Johannes Kepler, and Galileo Galilei. Galileo challenged dogma more than most by proving that the Earth orbits the Sun, and fell foul of the Church for his efforts.

The discoveries made by these scientists, and the methods they used, laid the foundations for the work of Isaac Newton in the following century, and also influenced philosophers such as Descartes, Spinoza, and Leibniz, who helped to shape the ideas of the Age of Enlightenment.

One Cause Only

Central to Aristotle’s philosophy was the concept of the “four causes” (see article). The new scientific methods of the 16th and 17th centuries rejected these, especially the concept of a “final cause”, or purpose. Instead it was proposed that there are only “efficient causes” in nature – i.e. physical causal triggers. Although this is closer to the modern idea of cause and effect, the idea had first been proposed by the Atomists some 2,000 years earlier (see article).

Laws of nature

The theories of Copernicus and his contemporaries heralded a new era of scientific discovery. Religious authority was undermined, but so too was the orthodox concept of the laws that governed the universe, which were based on Aristotelean cosmology and physics. In this new atmosphere of scientific enquiry, conventional assumptions were replaced with laws of nature derived from empirical evidence of observation and experiment.  

The New Method

Induction

Bacon described a method of scientific enquiry using the process of induction, inferring a general rule from particular instances. For example, the rule that water boils at 100C can be inferred because this is the case in every instance.

Experimentation

Often, it is not enough simply to observe in order to come to a scientific conclusion. The scientific method pioneered by Islamic philosophers involves conducting controlled experiments to get reproducible results.

Galileo Galilei once said: “In science the authority of thousands of opinions is not worth as much as the reasoning of one individual.”

Sunspots – The detailed study of sunspots made by Galileo and others showed that these are inherent features of the Sun. These observations contradicted the Aristotelean idea of the perfection of objects in the heavenly spheres.

Gravity – Although it may only have been a thought experiment, Galileo dropped two balls of different weights from the Tower of Pisa to show that they fell at the same speed. This refuted Aristotle’s assertion that heavy objects fall faster than lighter ones.

Elliptical orbits – Once it was proven that the Earth orbits the Sun, the orbits of the planets could then be explained. Kepler discovered that the orbit of Mars was not circular, but an ellipse, and concluded that all the planets had elliptical orbits.

THE GEOCENTRIC UNIVERSE

Outside the orbit of the Moon lies the celestial region in which the Sun, the planets, and the stars move in orbits at various distances from the Earth. Unlike the sublunary region, the celestial region is made from an incorruptible substance, which Aristotle calls the “quintessence”, or fifth element. According to Aristotle, the natural movement of the earthly elements is up or down, towards or away from the centre of the Earth. By contrast, the natural movement of things in the celestial region is circular. What’s more, earthly elements tend towards a position of rest, while celestial movement is unceasing. Thus, Aristotle reasoned that the stationary Earth, although imperfect, is at the centre of the cosmos.

Beyond the Moon’s orbit, Aristotle identified 55 concentric spheres to which the celestial objects are attached. As they radiate away from the Earth, the outer spheres draw closer towards perfection, stretching into spiritual realms that have no material existence. The universe, for Aristotle, is a perfect form, and cannot have come into being at any one time: it is eternal, unchanging.

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Psychology, Research, Science

Are male and female brains wired differently? 

GENDER BRAINS

Intro: It is often pointed where we differ, but when it comes to our brains, research shows that there are far more similarities than differences

WE are told that men and women are so different, it’s as if they came from separate planets. Martian men are stereotypically target-focused, assertive, and good at navigating; women born on Venus are more empathetic, caring, and expert multitaskers. We are all fascinated by what makes the other sex tick, but back on Earth, when it comes to brains, much of what’s been written about the sex divide is more science fiction than scientific fact.

Websites and news outlets have seeped scientific-sounding theories into common wisdom, such as the idea that women listen with both sides of their brain, whereas men use only one side; or that men and women navigate using “entirely different” brain regions. Some even claim that there is a “male brain” and a “female brain”.

These ideas often have their roots in scientific research, but much of it is based on early experiments in our brains which were either found later to be insignificant, or their results were misinterpreted or misreported.

Scientists are suckers for wanting to tell a story that will be the talk of the town – and the media are willing accomplices. Less headline-grabbing experiments that show little or no difference can get stuffed in the drawer, never to see the light of day.

So, what does the science really say? From the eighth week in the womb, little boys’ and girls’ brains do start to develop slightly differently. Throughout our lives, the sex hormones testosterone, oestrogen, and progesterone mould our individual physical and emotional development. Hormone level differences tweak the dial on characteristics such as aggression, pain threshold, stress response, and parent-child bonding, but each person is so unique that there is often more variation within each sex than there is between them.

Male and female brains don’t differ significantly in size, either. Men’s brains are slightly larger as a consequence of their larger bodies, and thanks to detailed scanning we know that some brain parts differ in proportion between the sexes, but the differences are too small to claim that there is such a thing as a “male brain” or a “female brain”.

Most areas of mental functioning, behaviour and personality are the same in both sexes. What differences there are, such as in aggression levels, are usually driven by the differences in sex hormones such as testosterone after puberty.

Nature or nurture?

Recent research points to the historic sex divide actually being down to society, not science. When the magnifying glass of science reveals the workings of the brain, the accepted male and female stereotypes mostly vanish.

Some scientists now think that what differences there are between male and female brains – such as, say, in map reading – are the result not of biology, but of thousands of years of brain-training. The good news, however, is the brain is brilliant at learning new things – you can adapt and learn many new skills within a lifetime.

So it is logical that, if given the opportunity, men and women can learn skills stereotypical of the other sex very easily. For example, children who are given Lego to play with are likely to mature and have brains which have larger spatial cortexes, regardless of whether they are male or female.

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Arts, Psychology, Research, Science

Memory and the functioning of our minds

HUMAN MEMORY

EVERYDAY functioning of our minds or how we make sense of the world is central to Psychology. Memory research, an area that has been explored since 1885, started when Hermann Ebbinghaus published Memory: A Contribution to Experimental Psychology. His was a lab-based approach where he set out to study our ability to memorise pure information, screening out the kinds of facts that people might already know would influence the experimental outcome. He designed trigrams, made-up syllables built from three letters – a consonant, a vowel, and a consonant – that had no meaning but looked like words. Ebbinghaus and an assistant carried out these experiments on themselves, learning the trigrams from flashcards, and varying the experiments to see what factors affected their capacity to remember.

This could be called a purely cognitive approach to memory – examining the way information is processed, memorised, and recalled. The work of George A. Miller forms part of this tradition, looking at how much random information we can remember in the short term, and how we can boost our ability to remember. The problem with this kind of approach is that in real life, as we all know, we don’t deal with meaningless information and there is a difference in what we remember when reading a book, tying our shoelaces, or recognising someone we know across the street.

Frederic Bartlett, another pioneer of research into memory, took a markedly different approach. Working in the 1930s, he became interested in how we organise our memories to fit in with things that we already know. Bartlett discovered that we adjust the material we hear so that it makes sense, deciding what to leave in and what to omit. His approach was more about how memory is adjusted in the light of human experience. There are parallels with this approach which can be seen in Freud’s theories about repression and the unconscious, and also in the research carried out by Elizabeth Loftus on eyewitness testimony.

Stubborn beliefs

Perception and cognition relate to what we take in from the world around us and what we make of it. While memory can seem a surprisingly slippery concept, so are the beliefs we hold – or think we hold. Faced with beliefs that clash – known as “cognitive dissonance” – we can end up unconsciously tweaking our beliefs, as if to restore order. There is a stubborn aspect to our belief systems, too. The concept of “confirmation bias” looks at how resistant we can be to information that conflicts with our most firmly held beliefs, and how this is even more marked when we are part of a like-minded group. And while we may claim to try to understand other people’s points of view, our default position, as Lee Ross’s “Fundamental Attribution Error” demonstrates, appears to be that we do no such thing. For example, look at some of the entrenched, anachronistic and insulting views held by some Protestant groups. Or certain factions that exist on social media.

The power of emotion

Understanding emotion, too, is also important: in particular, where it comes from. A century ago, the belief was that physiological changes in the body (like a surge in adrenaline) triggered our emotions. Now it is seen as being about how we interpret the situation in front of us, which is in part to do with the society to which we belong. This begs the question of whether emotions, and how we express them, are universal, or specific to certain cultures. Such questions recur throughout psychology.  

Over many decades of the last century, much of psychology was developed at Western universities, with experiments largely carried out on Western students, leading many to ask if this is a broad enough sample from which to develop universal truths about humankind.

Emotions also drives how we make decisions. Pure rationality would get us nowhere, because in every aspect of our lives we could find ourselves processing an infinite amount of information, but sadly lacking the processing speed of a computer. We need an emotional element to help us to rule out a whole bunch of options – helping us to make decisions based on gut feeling so as to be able to get on with our lives. And all this decision making can take a mental and emotional toll on our resources. As Roy Baumeister’s experiments appeared to show, it is possible simply to run out of the capacity to decide.

(Podcast ends)

A Short Biography of George A. Miller (1920–2012)

MILLER studied at Alabama, and gained his Ph.D. at Harvard. He began his research there in the 1940s, looking at speech production and perception, and his Language and Communication (1951) helped to establish the new science of psycholinguistics.

Building on existing mathematical theories of communication, he published a paper on short-term memory capacity, “The Magical Number Seven, Plus or Minus Two.” It captured the public imagination and even encouraged lively debates on the optimal length of telephone numbers.

He continued to work on the psychology of speech, testing some of Noam Chomsky’s theories, and in 1960 founded (with Jerome Bruner) the Harvard Centre for Cognitive Studies. He is regarded (with Chomsky and Bruner) as one of the founding fathers of cognitive psychology, the study of thought processes – a dramatic departure from behavioural psychology, which stated that since mental processes were not observable, they were not suitable for scientific study.

After a period at New York’s Rockfeller University, working on language acquisition, Miller moved to Princeton where he helped establish both the Princeton Cognitive Science Laboratory and WordNet, a word database that has applications in present-day search engines and artificial intelligence (AI).

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