Do Opposites Really Attract?

Hollywood loves the idea that opposites attract, but psychology and Jewish wisdom paint a more grounded picture.

The healthiest relationships are built on shared foundations and purposeful differences. Here are four key ideas that help you understand how this works.

1. Where similarities matter

Research consistently shows that similarity is one of the strongest predictors of long-term relationship stability. A recent study analyzed more than 79,000 couples across 22 traits.¹ The most highly related similarities between partners were their political and religious values and attitudes, educational attainment, and substance use.

These similarities matter because they reduce friction. When you agree on what matters to you and how you want to live your life, you spend less energy negotiating the basics. Shared values create a stable foundation for the relationship. They give you a common language for understanding each other and a comparable moral compass that guides your choices.

2. Complementary differences help couples thrive

Although similarity lays the foundation, certain differences can strengthen a relationship. Most studies find little, if any, similarities in a couple’s personality traits.² While differences in values can create conflict, this is not the same for personality traits, such as curiosity, openness, and self-discipline. And there is almost no relationship between personality differences and relationship satisfaction.² I

Differences in skills, strengths, and approaches can make the couple more effective together than either partner would be alone.

You might be someone who starts tasks easily while your partner struggles to finish them. You might be a planner while your partner is more comfortable improvising. You might be detail-oriented while your partner sees the big picture. You might be steady while your partner brings spontaneous energy. These differences create functional complementarity. Each partner’s strengths fill the other’s gaps.

3. What Judaism says

Judaism offers a profound lens through which to understand the interplay of similarity and difference. In Jewish thought, marriage is described as the reunion of two halves of one soul. This idea contains two essential truths.

First, partners share a spiritual essence. They are aligned in their deepest values, moral orientation, and purpose. This mirrors the psychological finding that similarity in core areas is essential for stability. You are not meant to marry someone whose values contradict your own. You are meant to marry someone whose inner compass points in the same direction.

Second, although the soul is one, its halves express themselves differently in the world. One partner may be more grounded while the other is more visionary. One may be more emotionally attuned while the other is more action-oriented. These differences are designed for growth. Partners refine each other and challenge each other, helping each other become more whole.

Marriage becomes a spiritual workshop where two people, similar in essence but different in expression, help each other become their fullest selves, together in partnership.

4. What this means practically

When you combine psychology and Judaism, you get a clear and practical framework for how to choose a spouse and sustain the marital relationship.

Choose someone who shares your life direction and moral orientation. These similarities create stability, trust, and shared meaning. They make daily life smoother and long-term decisions easier.

Appreciate differences that are functional rather than ideological. Differences in strengths can make the relationship more dynamic and resilient. Instead of seeing these differences as irritations, you can view them as invitations to grow. They allow each partner to bring something essential to the relationship.

Similarity provides steadiness. Complementarity provides growth. Together, they create a marriage that is both grounded and transformative.

1. Horwitz, T. B., Balbona, J. V., Paulich, K. N., & Keller, M. C. (2023). Evidence of correlations between human partners based on systematic reviews and meta-analyses of 22 traits and UK Biobank analysis of 133 traits. Nature Human Behaviour, 7(9), 1568-1583.
2. Leikas, S., Ilmarinen, V., Verkasalo, M., Vartiainen, H. L., & Lönnqvist, J. E. (2018). Relationship satisfaction and similarity of personality traits, personal values, and attitudes. Personality and Individual Differences, 123, 191-198.