This quote suggests that every person, at some point or another, contributes to or perpetuates falsehoods or illusions, often without even realizing it. This is not necessarily about lying in the conventional sense, i.e., deliberately telling untruths. Instead, it refers to the subtle ways in which we may distort or mask reality, usually as a means of conforming to societal expectations or norms.

The "false appearance" Thoreau speaks of could be interpreted in a variety of ways. It could refer to the facades that individuals put up to fit in or to avoid judgment or criticism. It could also refer to the illusions that society as a whole maintains, such as the belief in unattainable standards of beauty, success, or happiness.

In the context of today’s world, this quote could be applied to the phenomenon of social media, where people often present an idealized version of their lives, hiding their struggles and difficulties. This can lead to a culture of comparison and unrealistic expectations, causing stress and dissatisfaction.

In terms of personal development, Thoreau’s quote could serve as a reminder to strive for authenticity and honesty, both with oneself and with others. It suggests that one should question societal norms and expectations, and not blindly conform to them. It also emphasizes the importance of self-awareness and critical thinking in recognizing and challenging these "false appearances".

In essence, the quote is a call to resist the pressure to conform or to maintain illusions, and instead to seek and uphold truth, both in one’s personal life and in society at large.