Wednesday, 6 August 2014

The rationale for teaching by lecture


The lecture is not the ideal form of teaching - that is the prolonged one-to-one apprenticeship.

But the lecture has been found to be a very useful form of teaching (for certain purposes, within certain constraints) for many hundreds of years, and it has not been superseded by anything superior.

Indeed, there have been times and places in history when the lecture became the focus for teaching; and some of these times and places have been near the summit of educational excellence; for example medieval Paris or Oxford, of the 'Scottish Enlightenment' universities of the eighteenth century; both of which were lecture-focused systems, although with different forms of lecture.

Indeed, my own experience of the first tow years of medical school was of a lecture-focused system; and this was a very good experience (on the whole).

So, what is the rationale of lecture teaching?


The basis is that the lecture is a one-to-many method of education.

This is appropriate when the teaching has a large 'common' element which it is desired to be imparted to all students. Lectures would be no good if each student was pursuing an utterly different path, nor would they make much sense if all knowledge and understanding was regarded as 'optional'.

The lecture comes into its own as a form when there is a core of knowledge and understanding which it is intended that all of a group of students ought to share.


The lecture begins to break down, and become dysfunctional when there is too great a diversity of people in the class - too wide a range of motivation and ability.

(This break down of the educational process is, however, only apparent when there is a valid and precise method of examination. Otherwise it is easy to fool yourself that 'education is taking place'.)


Even at the best, a lecture can realistically only hope to satisfy about two thirds to three quarters of a class - some will find it too slow and dull, others too fast and difficult.

On any given day, some will be having a bad day (distracted, ill, worried, uninterested, uncomprehending...) and the lecturer may be having a bad day for similar reasons.

The best conditions for lecturing are when (among other pre-requisites) the majority of the class are attentive and want to understand and learn the material being presented; and this best applies when there is a good reason for the class to want to learn the material.

A proximate 'good reason' may be to pass the exams - that is necessary, but artificial; but the best reason (which leads to pressure tending to stimulate the best teaching) is that the class wants to learn the material in order to use it.

This is, indeed, the context for all the best higher and specialized education. Lacking which, teaching almost inevitably gravitates to being 'all about exams' - which pressure leads to inflation of qualifications, erosion of standards, and on a long-term basis allows non-teaching to masquerade as the real thing.



ElectricAngel said...

Lecture is/was a technology based on scarcity of materials. You needed to read the book aloud to the students because there might only be one copy of it in the whole country. It was a superb technology.

We are no longer suffering from insufficient educational materials. There are a plethora of sources now. What is lacking is a proper filter. The syllabus is a first-level filter.

The second level needs to be the professor, but it is pointless to serve as a source of information, especially in an age when the world's expert will fall behind the state of the art in the two hours he spends lecturing while the network advances. The professor, by guiding and probing individual students, and training them in doing this to each other, can serve as that valuable filter and mechanism. This cannot take place in a room of more than 20 students, however.

In a sense, this is good as it keeps the University from effectively running as a MOOC. MOOCs are great... For people who set up MOOCs. They use an obsolete technology that fails to make use of the chief reason students have always come to universities: intimate, in-class contact with a great mind.

If you would care to discuss further, leave a comment over at a post of mine and I will send email contact information, Dr.Charlton.

Bruce Charlton said...

@EA - Yes, I know all that stuff - it has been going the rounds since Marshall McLuhan and Ivan Illich - indeed since the radicals of the mid 19th century. What I am saying is that it just a theory, and it is wrong!

ElectricAngel said...

Make no mistake: students will love a good lecturer. My own feedback was "less of us, more you just talk." I have had to deprogram a bit. I think here of Joseph Campbell or Eugen Weber's recorded lectures, but then I had not had a book assignment: they just appeared on public television, back when I watched television.

I much prefer Socratic questioning, and for students to have done their assigned reading before I get to class. I also don't benefit from learning when the material goes one way only.

As to it's being only theory, I cannot say. I can compare sections and results between two professors using the two different approaches. I shudder to admit that the results in favor of experiential learning come from two sources, not necessarily connected to learning: positive student evaluations and (what is most important in the business of academics) higher continued enrollment.

I have tested a lecture-only format, a fully inverted format (students held accountable for doing the reading, and required to stage each class themselves), and models in between. The best results for students taking ownership of the material are obtained with a fully inverted classroom, but this model requires a tremendous investment of instructor time (about 30 hours for two sections I did once), and are at distinct odds with the needed for-profit model in higher education (in the USA, at least), where Freshmen and Sophomores sit in a lecture hall paying 600 chunks of tuition while one professor and 8 unpaid or low-paid teaching assistants bring them the course.

ElectricAngel said...

To quote another 60s fellow in this regard, the medium is the message. The large lecture hall format (and I note you were desiring to limit to 150) serves the needs of the same crony capitalist infrastructure that has Cathedral elites living large while immiserating the great body of people. Skim off all that tuition and you can pay for a LOT of fatcat salaries in administration. A pyramid structure like that will always attract shiftless bureaucrats and socialists who figure they can run the pyramid better without the need for profit.

My own experience in college was at a place that had large lecture classes only for some beginning science classes. I suspect it was because so many students signed up but then did not make it through science classes that the school figured that one large class was the proper way to sort. Now I wonder if the class structure itself wasn't what caused students who MIGHT have continued with science to decide that science was large and impersonal, and dropped out (of course, all but the first courses were groups of 20 or so.)

I recall one European history class with a very popular professor. Great lecturer. But passivating. I recall about a 1/3rd of the way through the course interrupting him to ask a question on a point, which he answered. I did so a few times through the trimester (odd little college.) I caught flak from fellow students for doing so, but the professor at the end-of-trimester tea party he threw for students thanked me; he never knew if people were engaged in the class, and at least knew I was.

They have the world on their phones, Professor Charlton. This means that if you want to reach them, you need to be better than the whole world, unless relying on the crutch of negative sanction through the grade. (When I coach faculty, I tell them that they'd better have the ego to think they are better than the whole world; I certainly do.) Once you're done fighting the world, you can flip the script: recognize that world and your students' place in it, your role as the critical filter that keeps them focused on what is important, and then turn THEM into filters for YOU, to serve as intelligent agents to help build your own body of knowledge. As Frost wrote, you'll "go to school, to youth, to learn the future."

Otherwise, you become the intellectual equivalent of John Henry, the man who fought the steam engine (he won the contest, and died immediately after.). Or, you become a fraud, using position and reputation to cover for the inability to exceed the capability of the machine powered by the Information Age. You're too valuable to us to exhaust yourself in this way, though the choice must be yours.

ElectricAngel said...

I refer you to this recent article that seems to notice that higher-education has a for-profit scam aspect to it, while the non-profit scam aspect is also present. since private owners cannot skim the profits,they go to administrators, like one law school Dean earning $870,000.

From the article (my bolding added): " InfiLaw does not disclose its finances, but law schools have traditionally been highly profitable enterprises. The reasons are straightforward: law schools are, or at least ought to be, relatively cheap to operate. The traditional lecture method of teaching allows for a high student ratio and there is no need for expensive lab equipment or, at free-standing law schools like InfiLaw’s, other costly features of university life, such as sports teams, recreational centers, esoteric subjects pursued by an uneconomical handful of students, and so forth. Indeed, until relatively recently, many universities treated their law schools as cash cows whose surplus revenues helped subsidize the institutions’ other operations."

Hierarchical pyramids invite exploitation by Cathedral-types.

ElectricAngel said...

One more link on the future of college. I excerpt the following from it.

The easiest way to picture what a university looked like 500 years ago is to go to any large university today, walk into a lecture hall, and imagine the professor speaking Latin and wearing a monk’s cowl. The most common class format is still a professor standing in front of a group of students and talking. And even though we’ve subjected students to lectures for hundreds of years, we have no evidence that they are a good way to teach.

Minerva is not a MOOC provider. Its courses are not massive (they’re capped at 19 students), open (Minerva is overtly elitist and selective), or online, at least not in the same way Coursera’s are. Lectures are banned. All Minerva classes take the form of seminars conducted on the platform I tested. ...

The Minerva boast is that it will strip the university experience down to the aspects that are shown to contribute directly to student learning. Lectures, gone. Tenure, gone. Gothic architecture, football, ivy crawling up the walls—gone, gone, gone. What’s left will be leaner and cheaper. (Minerva has already attracted $25 million in capital from investors who think it can undercut the incumbents.) And Minerva officials claim that their methods will be tested against scientifically determined best practices, unlike the methods used at other universities and assumed to be sound just because the schools themselves are old and expensive.

As they say in Silicon Valley, and as I teach on data, "in God we trust; all others bring data." (Note: they are probably atheists.) The university model of large lectures, made necessary by information expense and scarcity, will now be tested: is it more effective at having people learn (and having people learn, not having people teach, is the University's sacred mission) than small, focused seminars? As men of science, we must go with the data.

Bruce Charlton said...

@EA - "The easiest way to picture what a university looked like 500 years ago is to go to any large university today, walk into a lecture hall, and imagine the professor speaking Latin and wearing a monk’s cowl. (...) And even though we’ve subjected students to lectures for hundreds of years, we have no evidence that they are a good way to teach."

That is modernist evaluation in a nutshell. The fact that lectures were used for 500 years (actually more like 800 years) is regarded as *no evidence* that they are a good way to teach!

By contrast, some scheme dreamed up the day before yesterday is regarded as "scientifically determined best practices" - which they seem to suppose is a good thing.

Nuff said.