Here's a breakdown of the historical context:
* Horse-drawn carriages: The 19th century saw the widespread use of horse-drawn carriages for personal transport, public transportation, and goods delivery.
* Horse behavior: Horses are prey animals, highly sensitive to sudden noises and unexpected movements. These could easily spook them, causing them to bolt or rear, leading to accidents and injuries.
* Road safety: As a result, people were mindful of their behavior around horses to ensure their safety and the safety of others.
* The phrase itself: The phrase "not to frighten horses" became a common expression to remind people to be cautious and avoid sudden movements or loud noises around horses.
Over time, the phrase evolved to encompass broader meanings, representing:
* Courtesy and consideration: It became a general expression of being mindful of others, especially those who might be vulnerable or easily startled.
* Avoiding unnecessary alarm: The phrase also came to symbolize the importance of avoiding unnecessary worry or fear.
Therefore, the phrase "not to frighten horses" originated from a practical concern for safety in the horse-powered world of the 19th century, and its meaning expanded to encompass broader principles of courtesy, consideration, and avoiding unnecessary alarm.