Albert Einstein was a smoker, as were a lot of other scientists.

NASA mission control celebrated with cigars when the mission was successful...

From my own experience, smoking sometimes helped me improve concentration and it gave me a 10 minute cigarette break every hour or so, during which I could do some out of the box thinking on the problem.

Tobacco is like a close friend/advisor which is always with you.

Had it not been for the health issues it provoked in me (circulatory/heart), I would still be smoking today.

Even as a non-smoker now, I still respect the plant and I'm grateful for our relationship which lasted for 20 years.

I think it has greatly influenced our (human) development. This is very hard to measure or prove, of course, but given the mystical status that shamans attribute to it ("most powerful plant in the jungle"), I would suspect that it had something to do with the giant expansion of human consciousness that we've experienced since it was introduced into "our" culture.

Good or bad, we don't know, it just did, since so many people use(d) it.

Here's an interesting take on the subject: http://realitysandwich.com/217970/meeting-the-tobacco-spirit...

Note that the listed "virtues" are, in large part, descriptions of the relief of nervousness, irritability, and lack of focus resulting from nicotine cravings in nicotine addicts.

Addicts to many drugs experience similar relief when they consume the drug to which they are addicted.

Have you ever smoked tobacco? This isn't really true. Tobacco really does have psychoactive effects even before you are addicted. Yes, all things considered, tobacco is basically evil and should be replaced with something else, but it's not like people are just making shit up about how good it feels.

One would think that people in that era would have a lot more to be nervous and irritable about. It is actually soothing for those things even if someone is not an addict.

I would bet it's been replaced either in part or in whole by coffee. I know I drink coffee like people used to smoke (except at night when I switch over to tea).

That and electronic cigarettes.

I used to smoke just for the nicotine benefits. Then I realized that I stunk more than I thought so I quit that and picked up dip (smokeless tobacco). It provided a much more prolonged nicotine "buzz" and I could use it at my desk. The spit was gross but as long as no one was around, I could do it as often as needed and keep focused on my work. After a few months of doing it regularly, I noticed my front, lower gums were beginning to recede. I dropped that and went back to smoking every now and then but still hated the stink on my clothes, hands, face, etc. I bought a cheap ecig pen and liked the slight buzz I could get from the nicotine. After a few years, I've stepped up to larger devices to get a larger buzz. It's not the same as cigarettes or dip but I can use it with no mess or strong smell at my home desk.

A few years ago, I got a diagnosis of ADHD and medication was a recommendation. Generic amphetamine salts are what I use now, both an extended (20mg) and quick release dose (10mg). They made more of a difference in my focus than I ever thought. Only problem is that my mind turns into a bullet, I do whatever work I start on with little to no distraction but I can easy end up wasting time if I get sidetracked right as the medication kicks in. Nicotine still has its place for me, I use it everyday to keep awake and alert for my work. Medication is strictly for days where I know I have don't have time for distractions.

Coffee has a milder effect than the medication but it's a nice, quick boost in concentration and alertness that can get me through a class or meeting. I usually avoid drinking it on days I take medication as I tend to feel a very strained feeling, it's very unpleasant sensation and I become hyperactive and careless with my work. Nicotine and coffee have a complementary feel, they have different effects but they fit nicely together.

I think stimulants are my favorite thing ever. I wouldn't be anywhere close to where I am now in my career without their help. Most of my weaknesses come from procrastination now instead of both procrastination and being easily distracted. I'm getting better at starting things on time now and with the boost of focus, I don't take as long getting my work done than in the past.

Prescription painkillers and then later heroin seem to be the replacements when I look at the data.