and nobody's been arguing with you when you say things like "shrooms can cause you to freak out" or "research is uncommon" because everybody knows those things are true.  people are arguing with you when you say stuff like this:

"Both varieties ("natural" and not) have devastating effects on the brain, from short-term to long-term memory loss. Killing of brain cells. Destruction of myelin (the fat that makes your neuro processes work). Side effects, like I said, can include anything from mental retardation and permanent brain damage"

so, for the last tooth-pulling time, how do you know that shrooms - natural and not - have "devastating effects on the brain"?  how do you know this, which you state as a fact, if there's no research, except for the research i just posted which contradicts it?  personal experience?  

First, let me say why I'm saying you can't smoke that much pot. Reports vary on whether cigarettes or marijuana are more carcinogenic, depending on which chemicals in those drugs you believe to be the main carcinogen, the method of intake (and how long that chemical is held in the lungs, etc). For simplification's sake (and assuming you're not smoking out of a bong/bubbler/vaporizer/etc that will help purify the smoke), it would be safe to say that you'll end up with marijuana being about as carcinogenic as tobacco (even the most extreme estimate wouldn't put it much higher than 5 times). However, think that's on a per-ounce basis. Think about cigarette smokers' habits. They are smoking a pack a day, if not more. Even the most extreme smokers I know don't go above thirty bowls a day (and these people also all care about their weed enough to have bongs, etc, which take out a lot of the carcinogens). Furthermore, I would venture to say there is more tobacco in a cigarette than weed in the average bowl. Simply put, there has never been a recorded case of lung cancer from a pure marijuana smoker in history. Some of this may be because marijuana smokers tend to be cigarette smokers as well, but, where I'm from, health is emphasized, as are the greens, and there are many, MANY purely weed smokers. So I say you can't smoke enough weed to get cancer in the same way I say you can't smoke enough in a sitting to overdose. Technically, you CAN, even though there's a very low concentration of ?9-THC receptors in the brainstem and other critical centers; you just would have to smoke roughly 200 pounds in an 8 second interval, which would take many blowtorches, a bowl the size of a trampoline, and a sincere desire to die.

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Now, on to weed preventing learning. It's not that you won't learn AT ALL if you are high, or are a regular smoker (obviously). As for whether it is a temporary or persistent effect, users' ability to encode NEW memories returns to normal after approximately four weeks of abstentia (depending, obviously, on the degree of the users' habits, along with a few variable like body fat percentages). (I think, but am less sure, that marijuana inhibits memory retrieval as well, but I couldn't explain the mechanisms here, nor do I know the behavioral data, so I won't speak on that.) Memory may stay SLIGHTLY impaired for the chronic user (no pun intended), since, as said before, neuronal death has occured in potentially clinically significant amounts (and neurogenisis, if it occurs at all -- which is a huge topic of controversy -- is certainly limited), meaning cognitive performance globally won't be as high as it once was. (Interestingly, the neuronal death is why marijuana use actually IS linked to increased risk of Parkinson's -- ask if you want an explanation. But then again, to be intentionally crass, being stupid is actually somewhat of a risk-factor for Parkinson's).

Anyway, if you want the (shortened but still far too long) mechanism for why THC prevents encoding of new memory (which will hopefully help you understand, at least through analogy, why marijuana inhibits learning), I will offer this quick overview of LTP.

LTP (long-term potentiation) is believed to be the cellular basis of learning. Donald Hebb speculated long ago that, in order to have cellular learning occur, there must be a "coincidence detector" at the synapses -- something that would tell you that everytime presynaptic neuron A fires, postsynaptic B fires too, thus suggesting a strong connection between these two neurons. LTP -- which has a number of traits that make it attractive as this mechanism, such as associativity, cooperativity and specificity, all traits of learning (I'll explain if you need it) -- occurs when a high-frequency spiketrain (indicative of a strong stimulus -- remembering the all-or-none coding of action potentials) travels from A to excite B. The basis of this is that two types of receptors for glutamate -- the main excitatory neurotransmitter in the central nervous system -- exist (actually, there are more than two, but we only need to discuss these two here). These are NMDA receptors and AMPA receptors. AMPA receptors allow binding of glutamate always, whereas NMDA is normally blocked on the outside by a Mg2+ ion, too large to fit through the channel-receptor complex, but stuck because the cation is attracted to the negative resting potential inside the cell membrane of the post-synaptic neuron. However, as stated before, glutamate is excitatory (at least on AMPA and NMDA receptors), which means that, when AMPA binds glutamate, the membrane potential will depolarize. If a STRONG ENOUGH STIMULUS OCCURS, this will be enough to alleviate the force holding Mg2+ in place, thus freeing up NMDA receptors to be bound by glutamate. NMDA receptors, when bound, open up a channel that can not only let in the Na+ ions that lead to depolarization (as happens with AMPA receptors), but can also let in Ca2+, which is what starts "learning" through a biochemical cascade that leads to both pre- and postsynaptic morphological changes that lead to alterations in synaptic weights (i.e., certain synapses becoming stronger than others -- the neural network equivalent of a memory). This is how NMDA channels are a coincidence detector: They only open when: A) the post-synaptic cell is very active (since it had to be depolarized enough to let Mg2+ free), and B) the pre-synaptic cell is what is causing this (since glutamate must be present in the synapse to bind to the newly-freed NMDAR in order for Ca2+ to enter the cell).

How does THC affect all this? Well, THC is neither a pure depressant nor a stimulant. It really prevents any intense inputs from happening at all, keeping all neural circuits at a pretty level playing-field. This "equal ground" of activity across the brain is the enemy of a neural field trying to learn new memories by changing synaptic weights; if everything's firing equally (and at average intensities), then no learning or differentiation can occur. Actually, THC is an anandamide, a class of retrograde neurotransmitters that attach to presynaptic cannabinoid receptors. A typical endogenous example of this occuring is, for example, the presynaptic neuron fires glutamate, and, after the postsynaptic neuron binds some, it will send some 2-AG (an endogenous anandamide) back. This 2-AG binds to the presynaptic neuron and basically puts on the brakes: It tells it to stop releasing glutamate. It is NOT really used as an inhibitory transmitter in this sense, since it is only released AFTER the presynaptic cell has fired some. Again -- it simply keeps the amount the presynaptic neuron fires "in check," "leveling it out."

One more interesting fact about anandamides is that they are actually the retrograde transmitter used naturally in LTP's counterpart, LTD (long-term depression) -- the mechanism by which unnecessary neural connection are trimmed. In normal activity, this is as important has forming new memories in terms of creating a network that can accurately retrieve information (this can best be seen with PDP networks set up by cognitive psychologists who are interested in these issues). However, in the case of marijuana, you're likely encouraging a lot of LTD that shouldn't be taking place, trimming synaptic connections you might actually need (or at least a "normal" person would maintain).

Hope all this helps explain how marijuana prevents memory encoding. I realize it was pretty unclear, given that I wanted to give a quicker explanation without too much background (since I have no idea what you do and don't know about neuroscience and/or cognitive psychology already). If there's anything I can clarify, or anything else you're curious about, I can give it another try, or point you towards some real good, very simple textbooks (or more advanced ones if you're into that).

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And yes, the "SHROOMS MAKE YOU A DROOLING RETARD" argument was wearing on me as well. So stupid. Some people are just ridiculous. I can't believe that guy had the balls to continue to argue something so vehemently as if he knew when clearly all he had was rumor and urban myth (along with, possibly, some misunderstood information from his parents, who, based on his descriptions of their jobs, don't necessarily do anything all that related to what he was talking about, since I think the majority of at least neuropsychologists' work is actually behavioral, requiring ZERO cellular/molecular background, and, truthfully, I have never heard the term "neuropsychiatrist," and it sounds either made up or an excuse to call a psychiatrist something with "neuro" in it just to make his point that psychiatrist do indeed have to know a fair amount of neurochemistry.)

I fear any explanation will be lost on you.

I don't see a reason to get into a fight about this, because we really aren't disagreeing about anything, besides my disagreement with your reading skills and critical thinking abilities.

According to you, my final paragraph is "too opinionated," because I espouse the belief that "our economy would crash if pot was made legal." If you ask me, the only opinionated statement I gave was that I SUPPORTED LEGALIZATION OF MARIJUANA, DESPITE THESE ARGUMENTS.

What you are pointing to as "my opinion" was in fact a state of facts -- that an argument made by political philosophers based on social contract theory provides some justification as to why it is even within the government's realm of authority to ban a drug like marijuana. Now, I suppose it is my opinion that the argument is "logical," though I would like to hear an intelligent refutation of this point. However, it was NOT my opinion that this made marijuana criminalization laws a good idea.

Furthermore, even this interpretation of the social contract (as nyr2k2 points out, intelligently, there are many other interpretations) does NOT state ANYWHERE that, in order for the government to be concerned about an activity's effect on productivity, engagement in that activity must lead to ECONOMIC DISASTER. It is a poor attempt at debate to change the premise of an argument to the extreme version, point out that this extreme version DOESN'T happen, and then assert that the premise is false. Just because "all workers WOULD NOT be too lazy to work" doesn't mean that, on the whole, the average productivity of workers wouldn't decline if smoking marijuana became more prevalent. (The idea that smoking would become more prevalent if it were legal IS merely a premise about which you could have objections -- but again, it is NOT my opinion that it does or doesn't.)

"I'm sorry pot is not debilitataing. Just like anything else it is in how you use it. There is nothing wrong with someone working all day and coming home and smoking a joint. To suggest that by smoking this joint they will become lazy and ruin this country is crap."

And that paragraph's fantastic. If all people did was smoke a joint after work -- and only when they didn't have other obligations to get to, because THEN they would obviously abstain -- then, yes, you're right. Smoking a joint isn't going to be so, so bad. (Though you still might be underestimating the accumulation of THC if this were really that regular of a habit.) However, people aren't always as controlled with their herbal habits as you make it seem. Sure -- a glass of wine is great for your heart, so why do we even bother with liquor laws? I know many smokers -- including myself, so don't tell me I'm "like Alon" in that I'm speaking on a topic I know nothing about -- who find marijuana quite addictive, not PHYSICALLY so, but psychologically. If marijuana is freely available and in a person's possession, many people are quite inclined to smoke it. More and more often. It's habit-forming. You're making the assumption that every single person who has access to pot will smoke "a joint after work." I needn't even make the assumption that this is NOT the pattern of usage you will see in people across the board, since I can point to probably 50 people I PERSONALLY KNOW who don't use marijuana in this way (or I could just direct you to attend an N.A. meeting sometime).

Is pot debilitating? Maybe, maybe not. I've taken midterms and finals while high, written research papers, run my school newspaper, etc. I've also felt so lazy and apathetic that I've never gotten to work I wanted to accomplish, or gotten so distracted that it took me ten times as long to finish something than it should have. I can definitively tell you that I am much less lethargic and much more clear-headed and quick-witted at processing information since I've stopped smoking regularly. This is not to say that all people should quit. The value in being productive/thinking clearly is subjective, and it should be weighed by each individual based upon: 1) how much they value these things versus, e.g., enjoying life (I guess, unwinding, getting high, in this case), and 2) the degree to which smoking does result in these symptoms for a given individual. However, the fact that habitual marijuana users are less productive than they would be if they didn't smoke (looking at the stats as a group), due both to cognitive impairments and under-motivation, is pretty undeniable.

"So if you smoke weed you can't be a productive member of society?"

Again, Josh -- where do I say this? This seems to be more of your favorite argument style: Taking the absurd extreme of what someone says and then knocking this for being illogical. There are PLENTY of productive marijuana smokers, even more if you just count people who "tried" it. I have no idea where you got your list of famous people who did it. I would say much of this list is self-defeating as an argument, as all the presidents who you mention did not smoke pot during their period of productivity, as they chalk it up to "youthful indiscretion" (however much you believe that). In fact, the only person on the list who I would call a habitual user is Marley, and do you really think society would be running that well if Bob Marley were its pillar of productivity? However, I would still agree with you that smoking pot does not NECESSARILY mean you can't be productive. THAT is why I asked you not to give stupid anecdotes about someone who DOES smoke who IS productive; it tells you nothing. I know MANY prominent researchers who smoke. I can tell you that, for the older ones, at least, it most definitely HAS made them more scatter-brained and less productive. But it doesn't stop them from achieving SOMETHING special.

However, your argument ("I can name people who were productive AND smoked pot") is akin to my argument that strikezone judgment is irrelevant to hitting, since Vladimir Guerrero continues to mash in Anaheim. Or cigarettes don't cause cancer, since I have a great-uncle who smokes a pack a day, and he's healthy as can be. Or how about THIS comparison: I say "eating oily foods and sugars makes you fat," and you coming back with a list of ten people you know who enjoy potato chips who aren't fat.

Sadly, you accuse ME of having an opinion on this matter, when I hardly expressed one at all (and the degree to which I did, I shared yours). What makes me sad is that the REASON you read my post that way is because YOU have an opinion about the issue -- an opinion so strong that it prevents you from wanting to hear all the facts, consider all logic and intelligently discuss opinions other than your own because you are so defensive and threatened by these other view-points. To me, THAT'S more like Alon's statements: painfully unwillingly to leave your own biases out of an argument. I hope that, some day, you grow up to the point where you'll want to make a carefully reasoned argument for marijuana usage, one that considers the objections to your point of view and relies on better logic than the belief that rejection of your overstatement of the opposition logically leads to the conclusion that your argument (by exclusion of this overstated alternative) is right.

I'm swayze.