How do we know what our limits are? Why do we have to add a limit on ourselves? Society defines what we or we cannot: class, race, age, sex, and culture all have their limitations. The ones who looked beyond these made their dream come true. Very few of them were the reason for the mass change with their advocacy, writing, politics, or technological contributions.
We are what we think. Our thoughts define us. Our limitations or limitlessness depends on how we see our world.