search
Jonathan Sacks

Descartes’ Error (Chukat, Covenant & Conversation)

"We are becoming aware of the hugely significant part played by emotion in decision-making." - Rabbi Sacks (Image credit: The Rabbi Sacks Legacy)

In his 2011 bestseller, The Social Animal, New York Times columnist David Brooks writes:

We are living in the middle of the revolution in consciousness. Over the past few years, geneticists, neuroscientists, psychologists, sociologists, economists, anthropologists, and others have made great strides in understanding the building blocks of human flourishing. And a core finding of their work is that we are not primarily products of our conscious thinking. We are primarily the products of thinking that happens below the level of awareness.[1]

Too much takes place in the mind for us to be fully aware of it. Timothy Wilson of the University of Virginia estimates that the human mind can absorb 11 million pieces of information at any given moment. We can be conscious of only a tiny fraction of this. Most of what is going on mentally lies below the threshold of awareness.

One result of the new neuroscience is that we are becoming aware of the hugely significant part played by emotion in decision-making. The French Enlightenment emphasized the role of reason and regarded emotion as a distraction and distortion. We now know scientifically how wrong this is.

Antonio Damasio, in his Descartes’ Error, tells the story of a man who, as the result of a tumor, suffered damage to the frontal lobes of his brain. He had been known to have a high IQ, was well-informed, and had an excellent memory. But after surgery to remove the tumor, his life went into free-fall. He was unable to organize his time. He made bad investments that cost him his savings. He divorced his wife, married a second time, and rapidly divorced again. He could still reason perfectly but had lost the ability to feel emotion. As a result, he was unable to make sensible choices.

Another man with a similar injury found it impossible to make decisions at all. At the end of one session, Damasio suggested two possible dates for their next meeting. The man then took out a notebook, began listing the pros and cons of each, talked about possible weather conditions, potential conflicts with other engagements and so on, for half an hour, until Damasio finally interrupted him, and made the decision for him. The man immediately said, “That’s fine,” and went away.

It is less reason than emotion that lies behind our choices, and it takes emotional intelligence to make good choices. The problem is that much of our emotional life lies beneath the surface of the conscious mind.

That, as we can now see, is the logic of the chukim, the “statutes” of Judaism, the laws that seem to make no sense in terms of rationality. These are laws like the prohibition of sowing mixed seeds together (kelayim); of wearing cloth of mixed wool and linen (shaatnez); and of eating milk and meat together. The law of the Red Heifer with which our parsha begins, is described as the chok par excellence. As it is written:

“This is the statute of the Torah. (Num. 19:2)

There have been many interpretations of the chukim throughout the ages. But in the light of recent neuroscience, we can suggest that they are laws designed to bypass the prefrontal cortex, the rational brain, and create instinctive patterns of behavior to counteract some of the darker emotional drives at work in the human mind.

We know for example – Jared Diamond has chronicled this in his book Collapse – that wherever humans have settled throughout history they have left behind them a trail of environmental disaster, wiping out whole species of animals and birds, destroying forests, damaging the soil by over-farming and so on.

The prohibitions against sowing mixed seeds, mixing meat and milk, combining wool and linen, and so on, create an instinctual respect for the integrity of nature. They establish boundaries. They set limits. They inculcate the feeling that we may not treat our animal and plant environment however we wish. Some things are forbidden – like the fruit of the tree in the middle of the Garden of Eden. The whole Eden story, set at the dawn of human history, is a parable whose message we can understand today better than any previous generation: Without a sense of limits, we will destroy our ecology and discover that we have lost paradise.

As for the ritual of the Red Heifer, this is directed at the most destructive pre-rational instinct of all: what Sigmund Freud called thanatos, the death instinct. He described it as something “more primitive, more elementary, more instinctual than the pleasure principle which it over-rides”.[2]In his essay Civilisation and Its Discontents, he wrote that “a portion of the [death] instinct is diverted towards the external world and comes to light as an instinct of aggressiveness”, which he saw as “the greatest impediment to civilization.”

The Red Heifer ritual is a powerful statement that the holy is to be found in life, not death. Anyone who had been in contact with a dead body needed purification before entering the sanctuary or Temple. Priests had to obey stricter rules, and the High Priest even more so.

This made biblical Judaism highly distinctive. It contains no cult of worship of dead ancestors, or seeking to make contact with their spirits. It was probably to avoid the tomb of Moses becoming a holy site that the Torah says, “to this day no one knows where his grave is” (Deut. 34:6). God and the holy are to be found in life. Death defiles.

The point is – and that is what recent neuroscience has made eminently clear – this cannot be achieved by reason alone. Freud was right to suggest that the death instinct is powerful, irrational, and largely unconscious, yet under certain conditions it can be utterly devastating in what it leads people to do.

The Hebrew term chok comes from the verb meaning, “to engrave”. Just as a statute is carved into stone, so a behavioral habit is carved in depth into our unconscious mind and alters our instinctual responses. The result is a personality trained to see death and holiness as two utterly opposed states – just as meat (death) and milk (life) are.

Chukim are Judaism’s way of training us in emotional intelligence, above all a conditioning in associating holiness with life, and defilement with death. It is fascinating to see how this has been vindicated by modern neuroscience.

Rationality, vitally important in its own right, is only half the story of why we are as we are. We will need to shape and control the other half if we are successfully to conquer the instinct to aggression, violence, and death that lurks not far beneath the surface of the conscious mind.


[1] David Brooks, The Social Animal, Random House, 2011, x.

[2] Sigmund Freud, “Beyond the Pleasure Principle” in On Metapsychology, Harmondsworth, Penguin, 1984, p. 294.


Listen >
Watch >
Download the PDF:

Available in English, Hebrew, Spanish, French, German, Russian, Turkish, and Persian.

Family Edition: Read Here >


  1. How do you think emotion plays a role in decision-making?
  2. How does the Red Heifer ritual address the death instinct?
  3. Can understanding our unconscious mind help us control aggression and violence?

With thanks to the Schimmel Family for their generous sponsorship of Covenant & Conversation, dedicated in loving memory of Harry (Chaim) Schimmel.

“I have loved the Torah of R’ Chaim Schimmel ever since I first encountered it. It strives to be not just about truth on the surface but also its connection to a deeper truth beneath. Together with Anna, his remarkable wife of 60 years, they built a life dedicated to love of family, community, and Torah. An extraordinary couple who have moved me beyond measure by the example of their lives.” — Rabbi Sacks

About the Author
Rabbi Lord Jonathan Sacks (1948-2020) was a global religious leader, philosopher, the author of more than 25 books, and moral voice for our time. He served as Chief Rabbi of the United Hebrew Congregations of the Commonwealth from 1991 to 2013. Rabbi Sacks passed away in November 2020. His series of essays on the weekly Torah portion, entitled "Covenant & Conversation" will continue to be shared, and distributed around the world.
Related Topics
Related Posts