Wei Boyang

He is the author of The Kinship of the Three (also known as Cantong Qi), and is noted as the first person to have documented the chemical composition of gunpowder in 142 AD.

His Cantong Qi was probably written in stages from the Han dynasty onward until it approached its current form before 450 AD.

Wei Boyang was forced to hide in the mountains, there he focused on studying Taoism and refining elixirs.

The disciples then ask whether their master would take it or not, after which Wei Boyang says: "We went against society's customs and left our homes to practice in the mountains, without obtaining the way to immortality, we vow to never return.

The disciples discuss why practice alchemy for longevity when one dies after taking the elixir, whereas one would live for decades more without it.

The second disciple rebukes that Wei Boyang is no ordinary man, taking the elixir and dying must have been intentional.