If an oncoming car's high beams are on, is it acceptable to flash your high beams to alert the driver?

Flashing your high beams to alert an oncoming driver about their use of high beams is appropriate because it serves as a warning that can enhance safety on the road. High beams can cause significant glare and reduce visibility for other drivers, so notifying the oncoming driver can encourage them to switch to low beams. This communication helps ensure that both drivers can see clearly, minimizing the risk of accidents.

While it is important to do this with caution to avoid distracting the other driver, the act itself is a standard practice in many driving situations. Therefore, the response is validated by the principle of road safety and driver consideration.