To say what the Philosophers’ Stone – the great goal of alchemy – is, one has to know. And to know, one must have attained it. I cannot claim to have done this, so what follows must be speculation.
The mystery grows deeper the closer one attempts to look. Even to say what alchemy itself is proves difficult. Of course, everyone knows what alchemy is – or thinks he knows: it is an outmoded form of science in which men in conical hats cooked and mixed various strange substances trying to make gold out of base elements. Or they sought to make the Philosophers’ Stone, a substance that was supposed also to produce gold – and to confer physical immortality besides. This project was totally deluded, but somehow gave rise to modern chemistry with all its wonders and curses.