Bill Nye is sick and tired of people not wearing masks.

In two videos uploaded to TikTok mimicking the Consider the Following segment of his hit 1990s kids show Bill Nye the Science Guy, Nye demonstrated why masks are absolutely vital in the era of COVID-19.

Why do people in the scientific community want you to wear a face mask when youre out in public? Nye asked in the first video, answering: Face masks ... prevent particles from my respiratory system from getting into the air and then into your respiratory system. Blocking the movement of air is an old trick.

Nye went on to hold a scarf, a homemade face mask and an N95 mask in front of his face as he attempted to blow out a candle. The N95 mask was the most effective at restricting airflow and the scarf the least. See that video below:

The reason we want you to wear a mask is to protect you, sure, Nye said in the second video, which appears below. But the main reason we want you to wear a mask is to protect me from you and the particles from your respiratory system from getting into my respiratory system.

He then concluded with an urgent plea: Everybody, this is a matter literally of life and death. And when I use the word literally, I mean literally a matter of life and death. So when youre out in public, please wear a mask.

Nye has been a vocal proponent of masks since the coronavirus pandemic began, predicting that five years from now, it will be common for city dwellers to wear face masks in public , and that like other articles of clothing, these masks will be washable and reusable, but still effective.

Intuitively, if both people that is to say, the infector or infectrix and the infectee are both wearing masks, youve got to think youre coming out ahead, Nye said in an early June interview with The Washington Post .