On April 6, 1922 (just over 100 years ago), Albert Einstein clashed with the most famous philosopher of the day, Henri Bergson, about the nature of Time - in one of the most famous debates of the last century.

Einstein defended the picture he formulated in general relativity of time as inseparable from space and lacking the absolute reality that humans tend to perceive in it.

Bergson claimed that science alone cannot describe time, which he said was closely intertwined with the “vital impulse” of life and its creative expression.

The famous debate initiated a rift between physics and philosophy, “splitting the century into two cultures and pushing scientists against humanists, expert knowledge against wisdom.” (Jimena Canales)

Indeed, that is when people started to love physics and technology beyond what they bring as solutions into our world — but also to describe the world we can't see. Physics offered radical new perspectives on what lies beneath and behind our everyday experience. In this way, physics seemed like more than just knowledge; it seems like truth with a capital T.

But does that mean there is a philosophy — a "metaphysics" — that goes beyond what the math and the data support? And, if such background metaphysics exist, could it be wrong even if the theory itself is right in terms of experiments and data?

In the ensuing century, science and technology prevailed, leaving philosophy (and to some extent religion at least in the Western world) in a holding pattern, looking for its own meaning and diminishing role in society. And as a result, most of the developments in the twentieth century and to this day were related to technological improvements and step change, from cars to radio, from international flights to space travel, from TV to the Internet, until blockchain and AI, etc

The French philosopher Bergson was far more famous than Einstein in the first two decades of the 20th century. The reason most folks these days know Einstein's name but not Bergson's is an important story in itself and much has to do with that debate. It's the story of how science seemed to become the last word on everything, even on a topic as subtle, slippery and difficult to pin down as time.

In the debate, Bergson made it clear he had no problem with the mathematical logic of Einstein's theory or the data that supported it. But for Bergson, relativity was not a theory that addressed time on its most fundamental, philosophical level. Instead, he claimed, it was theory “about clocks and their behaviour”. Bergson called Einstein out for missing the distinction.

So, on that day in Paris, Bergson was not criticizing Einstein's theory. He was attacking a philosophy that had grown up around the theory — and that was being passed off as part of the science. It was the theory's hidden metaphysics that Bergson challenged. Bergson told Einstein that the only proper way to unpack the full meaning of time, in all its lived richness, was through explicit philosophical investigations.

Einstein, however, was not moved. In response to Bergson's challenges, the physicist lobbed his now famous grenade: "The time of the philosophers does not exist," he told the audience.

In relativity, space and time are no longer separate entities. Instead, they're replaced with a four-dimensional whole called space-time. But something very weird happens when you make that move. The remarkable thing about space-time is that it contains all the events that ever happened. It also includes all the events that ever will happen.

Being human, being at the centre of our own worlds, is an immense and beautiful mystery. The explanations of science are one route to plumb that mystery — but not the only route. The debris of that disagreement became the foundation of our present ideas about the fabric of existence.

But why this reflection is important after over 100 years?

Because that same rift needs to be closed now, as it is as important to do what is “good” for humanity (the land of philosophy) and what is “beautiful” (the land of aesthetics), while we ensure we do what is “right” (the land of science), particularly when faced with the upcoming risks for humanity caused by climate change and biodiversity loss.

Both Einstein and Bergson, beyond the debate and its immediate consequences, already understood that this was needed at the end of their lives, each reflecting on each other rival’s legacy — Bergson during the Nazi occupation of Paris and Einstein in the context of the first hydrogen bomb explosion. Science can well progress without philosophy, and sometimes can even have better explanations of the world around us, but philosophy and ethics are just as important, and need to always be used in conjunction.

We can design the best autonomous vehicle, but who will decide which obstacle to avoid between a child and an aged person, if both cannot be avoided? We can develop nuclear fission, but who is to decide when it is right to use them, if ever? We can use carbon-based solution, but what increase in temperature can we afford to accept? We can eat fish, but what fishing practices are acceptable, and which consumption is sustainable? We can develop DNA sequencing and manipulate our genome, but when is that acceptable to cure diseases and when is it dangerous as it changes the natural evolution of our species? And we could go on and on with questions that no science can answer, but only ethics can discern.

If we are to take the role of Homo Deus (as defined by Yuval Noah Harari) by pushing the boundaries of universal science and global technology that multiply our know-how capabilities, we better also know when and how is good to use them to avoid a significant fight back from our planet and our environment. And that only our beliefs or religion, our ethics and philosophy, and ultimately international agreement and laws will be able to contain and drive, rather than our understanding itself.

Now that we know the combined power of technology and capitalism, we need to pair them with philosophy and ethics to ensure that we apply them for the good of our society and for our planet, not just to maximize profitability of a company or achieve the best result only for a (small) portion of people.

Let us not forget that the value of science and technology is nothing if not paired with decisions made on what is good and bad for people and planet. It seems that the latest generations are better able than us to make these distinctions, and re-prioritize choices we gave for granted, preferring purpose to wealth and lifestyle to riches.

“With great power comes great responsibility”: Sustainability is the latest application of this old saying to our current reality. All those who work in this field should remember that debate between Einstein and Bergson, and recall that both sides have a reason to exist, better if they coexist and reinforce each other.

illuminem Voices is a democratic space presenting the thoughts and opinions of leading Energy & Sustainability writers, their opinions do not necessarily represent those of illuminem.