Jewish tradition regarding nature starts with Creation, in which God creates an orderly and beautiful universe and retains power over it. The Psalms are full of verses in which the natural world praises God because of this. So, in considering the natural and the man-made in Judaism, we give primacy to the natural because it is from, and sustained by, God.

But nature is not an end in itself. Humanity is needed to complete that which was created, to fill in gaps, enhance what is natural, and this enhancement must be done in service of God.

Consider the Tower of Babel. It was an engineering marvel, man-made, and made God angry enough to disperse its people all over the earth, speaking different languages. What made God angry was not that they built a tower, but that it was intended to be a tower up to heaven, to enhance the power and status of man, maybe even to rival God. So, according to Genesis, had the same tower been built but with the proper attitude, that is, as a monument to serving, God, we might still be speaking one language.

On the other hand, consider this story about a Roman consul’s confrontation with Rabbi Akiva over circumcision:

“The evil Turnus Rufus asked Rabbi Akiva, “Which are better, things made by the Almighty or things made by flesh and blood?”

He replied, “Things made by flesh and blood are better!”

…He [Turnus Rufus] said, “Why do you circumcise?”

…Rabbi Akiva brought him wheat and cakes and said to him, “These are made by the Almighty and these are made by man. Aren’t these [cakes] better than the wheat?”

Turnus Rufus retorted, “If God wanted circumcision, then why doesn’t the baby come out circumcised from his mother’s womb?”

Rabbi Akiva responded, “Because the Almighty [gave the] mitzvot to the Jewish People for [us] to improve ourselves with them.”
(Midrash Tanchuma, Parashas Tazria, 8)

In other words, the duty to perfect the world includes perfecting ourselves by performing mitzvot – commanded acts like circumcision.

As Hava Tirosh-Samuelson (Arizona State University) wrote in her book Jews and Nature in Historical Perspective: “The world created by God is good, but it is not perfect; it requires human action to perfect it in accord with God’s will. While nature is not in itself holy, it can be sanctified through performance of prescribed commands from God, the source of holiness. In Judaism, the system of revealed commandments stands in contrast to nature, prescribing what should be done to that which already exists.”

This outlook means that the study of the natural world is not inherently in conflict with Jewish law. In fact, we are expected to use the knowledge gained thereby to bring us closer to God. Accordingly, ancient and medieval rabbis and Jewish philosophers saw both scientific knowledge about the world and Jewish law as manifestations of the wisdom of God, and they work hand in hand.

Think about the laws concerning the construction of the sukkah. The greenery on the roof of the sukkah, the s’chach, must be something that has grown from the ground that is now detached from it. What if you have processed it in some way? That depends on how and to what degree. For example, if you use cut branches of flax, that’s OK.

But, according to Maimonides, as he wrote in the Mishneh Torah (Sefer Zemanim, Sukkah-vLulav, translated by Eliyahu Touger) if they’ve been crushed and combed  – steps on the way to making linen – then they can no longer be used for a sukkah, “since its form has changed and it is as though it is no longer a product of the earth.” But one “may use ropes made from palm bast or hemp and the like as s’chach, since their original form is unchanged.”

That is not a universal opinion. There are different opinions concerning how much processing is too much. It’s a matter of rabbinical judgement. But the sukkah also shouldn’t be 100% natural, that is, arising by itself with little or no human intervention; say, if you make a hollow in a pile of corn stalks and try to use that as a sukkah, that’s not kosher.

The walls of a sukkah, in fact, can be made out of pretty much anything: also according to Maimonides, “The walls of the sukkah are kosher [although made] from all [substances]. All that is necessary is a barrier of any kind. Even living beings [may serve that purpose. Thus,] a person can create a wall [of the sukkah] by using a colleague… serving as a wall.” (I’m sure most of us can think of a colleague we’d like to draft for this purpose.)

A mixture of natural and man-made materials can also be OK: “If some of the walls were the result of human activity and some were trees, we consider [its structure]. We may ascend to any [sukkah] where, if the trees were taken away, it would be able to stand with the walls that were built by man alone.” Here it is the man-made component that determines whether a sukkah with a mixture of natural and man-made wall components is kosher.

Maimonides strongly and matter-of-factly promoted integration of the natural and manmade, both in his writings as a rabbi and philosopher, and in his practice as a physician. In the words of Dr. Sherwin Nuland, “Maimonides would want to be thought of as a bedside physician who used the ethical principles both from Hippocrates and from Judaic beliefs taken from the Torah and Talmud… The doctor, as he saw it, was an agent of God, and providing people with health care was a way of finding God and a way of leading people to the moral life.”   Doctors are obliged to treat anyone who comes for treatment. And anyone who is ill is obliged to seek medical care. You’re also required to live a healthful life. That way, you are able to serve God through the mitzvot.

For Maimonides, science and Jewish commandments both come from God, so there is no conflict between them. If there appears to be a conflict between rabbinical pronouncement and some physical observation, Maimonides says to give credence to the physical observation, that the apparent conflict probably occurred because the earlier rabbis had insufficient understanding or maybe did not have the scientific and mathematical tools that later became available.

What about cutting-edge medical and surgical interventions beyond mainstream practice? Certainly, artificial organs, the development of new surgical techniques, bioadhesives, pace-makers, and the like are all man-made and Judaically acceptable. But how far can we go? Is genetic engineering, for example, going too far, changing the essence of Creation?

If the genetic engineering is pursued in order to find cures, great. Therapeutic genetic engineering and gene therapy are OK. The use of scientific knowledge to heal is supported by biblical, Talmudic, and rabbinic teachings.   Some of these analyses are ingenious. Maimonides, for instance, uses the biblical obligation to restore a lost object (Deuteronomy 22:2) to include the restoration of one’s lost health (Mishnah Commentary, Nedarim 4:4). What about genetic screening for diseases that currently have no effective treatment, like Huntington’s disease? That’s not clear. There’s concern among the rabbis about the emotional burden a positive result could place on the person getting tested.

Certainly, the production of therapeutic substances like antibiotics and insulin by recombinant DNA technology is allowed. And when gene therapy becomes available to repair defective genes that cause hemophilia or Huntington’s or sickle cell anemia, that should also be Judaically permissible.

How far can we go? Treating, curing, and preventing disease are OK. Genetic tinkering to modify human traits like height or eye color, probably not. Jewish law could also bump against issues such as the amount of genetic modification needed to change the identity of a species of plant or animal, and the ramifications of this for kashrut. Rabbi Immanuel Jakobovits cautioned (Jewish Medical Ethics, 1975):

It is indefensible to initiate uncontrolled experiments with incalculable effects on the balance of nature and the preservation of man’s incomparable spirituality without the most careful evaluation of the likely consequences beforehand … ‘Spare part’ surgery and genetic engineering may open a wonderful chapter in the history of healing. But without prior agreement on restraints and the strictest limitations, such mechanization of human life may also herald irretrievable disaster resulting from man’s encroachment upon nature’s preserves, from assessing human beings by their potential value as tool-parts, sperm donors or living incubators, and from replacing the matchless destiny of the human personality …by …soulless artificiality.

We always need to go back to intent. Human manipulation of what is natural must be in the service of God. What is our goal in introducing new processes, techniques, or materials to the world? Is there a clear benefit to mankind? I’d like to conclude with a midrash on human responsibility toward nature1:

The Holy Blessed One took the first human and passing before all the trees of the Garden of Eden said: ‘See my works, how fine and excellent they are? All that I created, I created for you. Reflect on this and do not corrupt or desolate my world; for if you do, there will be no one to repair it after you.’

Nature is our starting point. Judaism commands us to enhance it according to Jewish law. The two, natural and man-made, work together in the service of God.

(This post is part of Sinai and Synapses’ project Scientists in Synagogues, a grass-roots program to offer Jews opportunities to explore the most interesting and pressing questions surrounding Judaism and science. This post is adapted from a talk given at Congregation Adas Kodesch Shel Emeth in Wilmington, DE).