The Nobel prize for proving the existence of molecules was awarded in 1926. Less than 100 years ago. Our understanding of physical chemistry is extremely recent.

In the absence of firsthand accounts, historical sources become our sole means of understanding past events. This transition typically occurs within two generations, or roughly 50 years, of the event's occurrence.

The oldest living person today was born the same year Thomson published The Corpuscular Theory of Matter in 1907. So a long time ago in one sense, but not so long in the scheme of things.

Rome was about 2500 years ago.

The first recorded name, 5000 years.

Oldest human structures 10k years.

Humans, about 130k years.

Our oldest "ancestors" 300-400k.

3.7 billion years.

For you, not so recent. In the grand scheme of things it was a heartbeat ago.

That’s more than a hundred years after Franklin.