The triangle tattoo with an eye inside is widely known as the “all-seeing eye”. It is generally thought to represent spiritual, mental, and physical vigilance. It symbolizes the ability to observe and be aware of all things both seen and unseen. It is often used to denote that the wearer is the protector of the secret knowledge, or has the power to see things others don’t. Generally people who have this kind of tattoo often have strong spiritual beliefs and are in tune with the universal energies and mysteries.