Behavioural Contagion

Behavioural contagion is known as the spread of behaviours through population or exposure. Are our behaviours mimicked from those around us or do they come from within? As a society, our tendency for homogeneity is no surprise. Sometimes, we may not even realize we are behaving a certain way. Science says we may be doing so because we saw someone else engaging in the same behaviour. Hence we were influenced to do the same, a phenomenon known as behavioural contagion.

Behavioural Contagion and Judaism

The word contagion comes from the word contagio, which means from touch. Contagion refers to transmission through touch or contact (Marsden, 1998). Behaviours can be spread as quickly as diseases. Should we choose a negative environment for ourselves, our mental and spiritual health will be greatly affected. Rabbi Eliyahu Dessler, Talmudic scholar and thinker, cautions a person from breathing in the air of a negative environment, comparing it to a contagious disease. He quotes the words of Nachmanides in his book Strive for Truth, Part Two, on page 177,

“To look at the air of a place affected by pestilence or other contagious diseases is dangerous and may cause one to catch the infection; to think about them may have the same effect. This is why the man afflicted by leprosy must live in isolation.”

Rabbi Dessler continues, that in our physical world, microbes, which float in the air, have the ability to cause disease in humans should they be inhaled or ingested. Spiritual disease is no different and inevitably affects a person on contact or sight. Should a person make the decision to remain part of a negative environment, he will eventually become morally corrupted and spiritually diseased.

Maimonides and Behavioural Contagion

As children, being influenced by moral examples can be invaluable. We can be molded with good character traits. Even as adults, we should not underestimate the importance of being influenced by moral examples in our lives.  Maimonides, a respected Jewish philosopher and physician, writes that heredity affects human behaviour significantly less than social interactions. Maimonides therefore recommends that we seek teachers, mentors, and friends who can help uplift us in our daily lives and conduct, even paying for the opportunity if necessary in order to be influenced by moral examples.

Make yourself a teacher; acquire a friend; and judge every person favorably. (Ethics of the Fathers 1:6)

Maimonides also advises against associating with unethical friends due to their harmful impact on human character. If there are no ethical people with whom to associate with, Maimonides advises dwelling alone in a cave, rather than succumbing to negative social influences.

Distance oneself from a bad neighbor, and do not befriend an evil person. (Ethics of the Fathers 1:7)

Although our behaviuoral contagion may prove to be positive, there must also be meaning in the things we are doing. If we are only doing things because someone else is, we are essentially robbing our lives of meaning.


- The Kotzker Rebbe

It is important to take initiative and be the one to start things. We don’t have to wait for someone else to. When we do things from our own initiative and not because someone told us to, we are elevating ourselves to a higher spiritual level. Our behavioural contagion will reach much farther, and influence others to do the same.