The re-invention of a military-only antiseptic into "bedside penicillin for all" creates a global beacon of hope for a world at war

the tiny stone the builders rejected

Despite the self-centred claims of physicists, the greatest benefits to humanity have generally been ardently pursued (invented), not accidentally stumbled upon (discovered).

DNA was discovered in 1860s by an Swiss doctor, but for most of us, it was really only discovered 125 years later in the late 1980s.

That was when it began to first be successfully used to solve unsolved criminal cases, when British researcher Alec Jeffries re-invented 'DNA' as a means to definitely identify biological evidence left at the scene of a crime.