I often come across the argument that we are about to experience a “4th Industrial Revolution”. Here’s one example, just from today:

I think this is wrong, both in description and chronology. And I wish economic historians and the commentariat could settle on definitions that are both historically accurate and analytically useful.

First off, why is it wrong?

Just a few (of many) reasons, mostly involving problems of timing and inaccuracy.

It implies that the first IR started with the steam engine, thus placing far too much emphasis on coal as an explanation for its origins. To be fair, it’s better than others because it mentions water and mechanisation too, but if so, why choose 1784 as the starting point? If you’re going to do that, you could push it decades back.

And let’s not forget that the British Industrial Revolution was the invention of invention. So perhaps we shouldn’t just be concentrating on only a few general-purpose technologies (GPTs). If you are going to look at GPTs though, this should be done with accuracy. “Division of labour” seems a bizarre one to put in the 2nd IR (I assume they mean Ford-style assembly lines?). Surely it should be earlier given Smith was writing about it in the 1770s. If anything, division of labour is what accompanies many technological changes rather than a GPT in and of itself.

A similar attempt by Gordon, placing steel production as part of the 1st IR (1770-1840 for him) has the dates off completely. You might go with Benjamin Huntsman’s crucible steel which was much earlier, in the 1740s, but actually you’d want to go with Bessemer’s converter (patented later, in 1856), which actually brought on the transition to mass production (watch this video of it - it’s one of the coolest things ever invented).

So what should be the standard?

There are two possibilities.

1. One is to accept that the Industrial Revolution was an acceleration of innovation - the birth of modern economic growth. As such, it never stopped, and we’re still living through it. This has several analytical advantages, the main one being that it forces us to think about the general sources of innovation rather than what led to specific developments. It also prevents us getting hung up on explanations of the IR that don’t quite work (i.e. that coal caused the IR) by underscoring the fact that the IR was a generalised wave of innovation, applied to all industries, from advertising to actuarial science and agriculture, as well as to iron, cotton and steam.

2. The other is to devise something more accurate, that focuses on complementary GPTs in materials, techniques and energy in particular. I would also add transport, communication and perhaps medicine and food to that list for their large knock-on effects. Here’s a sketch of what I mean, with occasional illustrative examples of prominent inventors in brackets, and approximate dates (I’m less clear on the later stages, so please be a little forgiving):

1st IR (1650-1820): instruments & measurement (Huygens, Harrison, etc), mechanisation, tools and factories (Arkwright, Boulton, Bramah, Brunel Snr), water power (Sorocold), civil engineering (Yarranton, Smeaton, Brunel Jnr), iron (Darby, Cort), inoculation and vaccination (Montagu, Jenner), early steam power (Savery, Newcomen, Watt, Trevithick), early chemicals and rubber (MacIntosh), food canning (Donkin)

2nd IR (1820-1870): coal gas for heating & lighting (Accum, Malam), steam engines for transport on land and sea (Stephenson, Pettit-Smith), precision tools for mass production (Maudslay, Whitworth), steel (Bessemer, Siemens), mass hygiene and sanitation (Arnott, Pasteur), mass industrial and agricultural chemicals including plastics (Lawes, Parkes), electric telegraphy (Cooke, Wheatstone, Diamond), hydraulic cement (Aspdin, Johnson), refrigeration (Harrison)

3rd IR (1870-1914): mass electricity and its applications (Edison, Bell), early oil for transport (Benz, Diesel), production line (Ford), chemical fertilisers (Haber), early flight (Wright), mass vaccination (Pasteur), mass steel use

4th IR (1914-1970): mass home machinery (i.e. washing machines), mass oil transport use, antibiotics, early computing, early mass electronic devices (i.e. TVs), early space flight, early non-fossil power, green revolution, mass plastic use

5th IR (1970-?): mass silicon use, mass electronic devices, robots in production, mass flight, mass internet use, early communication-enabled asset sweating (i.e. sharing economy)

6th IR (?) all speculative: mass computed industrial use of additive manufacturing (i.e. robot-designed and 3D printed buildings), bio-manufacturing (i.e. applying agriculture to industry), mass space flight, mass renewable power and storage, mass home robots, engineered medicine (i.e. programmable viruses), slowed ageing, automated transport, mass asset sweating