The notion of three being a mystical number became a topic in psychology by examining the psychological impact of numbers. Research conducted by Dr. Salkind in 1972 showed that the number three was associated with happiness when it came to people's perception. He found that individuals who had more positive attitudes toward life were likely to have three main positive aspects in their lives and vice versa. In addition to Salkind's study, other studies have supported the idea that the number three plays a significant role in the human psyche.

Although Salkind's findings may have sparked the modern fascination with the number three, the idea of three objects going together can be traced back to ancient Greece. According to Pliny the Elder, three is the magical number of the universe, as described by the philosopher Heraclitus. In his celebrated philosophical work, Heraclitus said that all things in the world are in a constant state of change and that only the universe remains unchanged. Heraclitus' thoughts about the number three are reflected in many other ancient cultures, including China and India.

The significance of the number three is also evident in various aspects of technology and design. For instance, the concept of the "triad" in art and literature, which originated in the 1940s, has become a foundational element in many works of art. The use of the triad in contemporary music, design, and visual arts indicates a trend towards seeking harmony and balance through the combination of three elements.

In the realm of technology, the three elements mentioned are typically two primary components and one secondary or supporting component. This concept can be seen in the design of smartphones, which typically include a front-facing camera, a display, and a processor, with additional features such as memory, battery life, and connectivity.

When discussing things that go together, three elements that are commonly mentioned in psychology and popular culture are health, wealth, and relationships. These three aspects of human life are often seen as interconnected and influenced by one another. For example, good physical health may lead to improved mental and emotional well-being, while financial success can provide comfort and security. Relationships, in turn, serve as the framework for building connections and maintaining strong interpersonal bonds.

There are numerous activities and hobbies that involve the concept of three. Many sports and outdoor activities are practiced in threes, such as swimming, cycling, and running. These activities not only improve physical health but also foster a sense of community and camaraderie. In the realm of leisure time, individuals may enjoy activities such as playing a musical instrument with friends or participating in group fitness classes. These experiences allow people to connect with others, develop a shared passion, and establish a sense of belonging.

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