I found The Freedom of Choice to be a great book overall, however I have a question regarding a possible contradiction.
You state that drug use is one of the only things that halts development. Yet the only example you gave of such was two kids who used psychedelic mushrooms. You yourself stated that mistakes need to be made in order to be learned from. Don't get me wrong I'm not saying drugs do not hinder you in any way but to say that the damage is irreversible seems to me to be a stereotype. How can you speak for every individual circumstance? And just out of curiosity have you yourself taken drugs before to know that they will damage you beyond repair?
Just because two kids on mushrooms claim to be dolphins doesn't mean all hope is lost for everyone else who's made a few mistakes. I do not mean to sound so defensive, I'm only curious as to your thoughts. I admit there may be something I'm not seeing.
I have never taken drugs, simply because I have never seen any point of becoming more stupid than I really am.
I am vividly aware of my current limitations and it just doesn't make any sense to me to cripple my intellectual abilities any further. My direction is exactly the opposite - the development of Intellect - increasing the Ability to Understand.
It is true that we learn best from mistakes. But they do not need to be our OWN. We can use our intelligence to learn from mistakes of others. In fact, learning is just as effective if we observe consequences of choices of other Individual Intellects, including The Great One.
Trying out things is fine, but as soon as you conclude that something constitutes a mistake - you should TAKE STEPS NOT TO REPEAT IT.
Whether or not "all is lost" as you say - depends ONLY on your attitude. You have The Freedom of Choice. Can you improve CHOICES that you make?