In 1665, the bubonic plague was ravishing London. About 15% of the population died. Entire villages went into lockdown. Institutions and of course businesses were being closed down for one reason or another. One of those institutions was the University of Cambridge. There are tales of people losing their minds from the response to the plague and committing suicide.
One young student took advantage of the situation. He took whatever books he could carry and retreated to a small village called Woolthorpe in the relative safety of the countryside. He took the opportunity to work on his ideas and read books outside the usual highly structured and onerous curriculum. Most importantly he had time to think.
His window overlooked an orchard. Later in his life, he shared how he had watched an apple fall from the tree outside his chamber window, and in his mind, he questioned why it fell straight to the ground.
In answering that question, he theorised that everything in existence is attracted to everything else, and this attraction, the force of gravity, ties the universe together. The young student was of course Isaac Newton.

It was during this time that he first developed a mathematical formula for gravity and the foundations for Calculus. The sciences of mathematics and physics lept forward more during this time than any other time in history.
Without going into lockdown Newton would have continued his studies as per usual. His time would have been spent on doing what was laid out before him. As a brilliant man, he no doubt would have been successful anyway. However, the lockdown, despite the enormity of their inconveniences at the time, provided an opportunity for Newton to develop something truly extraordinary that changed our world forever.
There were some students who responded to the plague and the consequent lockdowns as an unredeemable setback. So much so that they felt their lives were over. Isaac Newton seized the opportunity it offered and created something truly wonderful that we all benefit from today.
In 2021, many of us have found ourselves with a new plague called Coronavirus. Fortunately, this plague is much less fatal and our ability to respond to it and manage communicable diseases have improved since 1665. Nonetheless, many of us are still finding ourselves in regular lockdowns in response to this disease. We can choose to see this as a set back. Or, we can choose to use the opportunity to work on something different like Isaac Newton did.