There is a small, yet growing subfield within psychology called color psychology. Researchers in this field are interested in how people perceive, relate to, and respond differently to various colors. Some reactions that we have to colors may be based on biology. For instance, since blood rushes to the face when one becomes aggressive, the color red, in both humans and animals, is a signal of dominance. Other reactions to colors may be based on a learned association between the color and another object. For instance, a Yankee fan may feel happy when seeing blue pinstripes because he or she associates that color scheme with the team.
Towards the end of Parshat Shelach we are informed of the mitzvah of tzitzit. We are commanded to place fringes on our garments, including a thread that istekhelet. The purpose of doing so is stated explicitly within the pesukim, as they function to remind us of G-d’s commandments and not to wander after our hearts and eyes. Later authorities debate the exact color of tekhelet. Some say it is blue, some violet, and some green. Others debate how many strings have to be tekhlet and how many are to be white.
How exactly does wearing fringed garments remind us of the mitzvot and prevent us from wandering after our hearts and eyes? Numerous explanations have been given, some focusing on number symbolism, others on the significance of garments, and still others on the importance of color. Focusing for now on this last category, the question becomes more specific: how does wearing blue/violet/green strings interspersed through white strings, remind us not to sin?
Rabbi Meir (Menachot 43b) tells us that looking at tekhelet sets off a string of associations that keeps us from sinning. Tekhelet, which he seems to understand as being blue, is a similar color to the ocean, which is a similar color to the sky, which is a similar color to G-d’s Throne of Glory. Ramban adds that within the word tekhelet are the words kol (all) and tachlit (purpose). Meaning at its core tekhelet reminds us of our mission in this world, which is to serve G-d by doing mitzvot and avoid sinning.
Writing in the 15th century, Rabbi Isaac Arama suggests that there is another important moral significance embedded within tekhelet. The message is dependent on a medieval color theory which is not followed in modern times. The assumption was that there were seven colors that flowed on a spectrum: white, yellow, red, green, blue, purple and black. At the extremes of the spectrum were white and black, and sitting in the middle was green. Rabbi Arama, presumably understanding that tekhelet is green, argues that the symbolism behind tekhelet is that it is the middle ground between extremes. This serves as a model for our character traits that we should follow the middle path.
Using Rabbi Arama’s precedent to interpret the message of tekhelet based on the color science of his time, perhaps there is another layer to tekhelet that we can add by viewing it through the prism of modern color psychology. In a fascinating article researching how colors impact marketing strategy, Lauren Labrecque and George Milne summarize previous findings as to the psychological significance of different colors. White, the total reflection of all of the colors, is associated with sincerity, purity, and peace. Blue, which along with violet represent the shortest wavelength of all of the colors, is associated with intelligence, trust, and duty. In contrast, colors on the longer end of the wavelength spectrum (like red, orange, and yellow) stimulate states of excitement and arousal, oftentimes emotions related to sin.
As the pesukim indicate, tzitzit function to counteract sin. Presupposing that tekhelet is blue, perhaps the duty and loyalty invoked by seeing blue and the purity associated with white, are meant as a counter to calm the excitement represented by the red of sin. In addition to the associations that lead to us to think of G-d’s throne, the psychological symbolism of the colors themselves may serve as an intervention to arrest the arousal of sin and remind us to be loyal to G-d.