One thing I've been thinking about a lot lately is how I now believe theory ("common sense" might even be a better word) matters more when making assumptions and trying to understand information than actual data in many situations. This is the opposite of what I've always thought and been told, as anyone who studies science is usually told "let data do the talking." In a perfect world, I agree. The problem is the world and the people running it are far from perfect.
There are a few problems with looking at data. The first is studies for the data are usually funded by people with objectives. For example, suppose I represent the wheat industry in the Untied States. It's very reasonable for me to fund a bunch of studies for the health effects of "whole grain wheat," and only publish the ones which show wheat in a favorable light. Once enough data gets out there it becomes dogma. Nutrionalist will confidently believe wheat is healthy, and any data which disagrees with them and says "no wait it's actually bad" will usually be silenced since people don't really like being proven wrong, especially when it will have a negative impact on their career. The general public wanting to eat healthy make the mistake of thinking they have access to a bunch of useful data from experiments, but instead it is extremely filtered data which just reflects the objectives of people funding the studies. They are the ones who suffer.
Another thing which makes data matter less is people usually aren't able to objectively analyze complex and important situations and almost all data must be interpreted. One question I've asked when I found out affirmative action is a HUGE!! factor for getting into medical school is "Why are we assuming over-represented minorities don't just have some natural genetic qualities which make them better suited for medicine? Why are we assuming all races are perfectly equal in every way and if they aren't all equally represented something is wrong? We should just take socio-economic conditions of an applicant into account, who cares about race? That will ultimately favor underrepresented minorities anyways since they have a lower socio-economic background." I approach it in an incredibly friendly manner and anyone that knows me knows #1) I'm not a racist in the sense that I think there is a superior race or people should be treated differently, #2) I don't think whites (I'm white) are the smartest race and I don't really give a shit where they rank. I give a shit about having policies which don't make for the best doctors and make it extremely unfair. You're likely not aware, but if you are an Asian American it is so, so much harder to get into medical school than if you are a Black American.
Since expressing my opinion, I've been called a neo-nazi, white supremist, retard, etc. Since I actually research topics when I'm told I'm wrong, I've since learned I've been told an incredibly lot of incorrect facts, such as "intelligence isn't inherrited" (it is) and "studies have shown you can't show the race of a person through their DNA" (you can) and "studies which test IQ from people with different socioeconomic backgrounds all show people having the same IQ" (they don't and it's not close).
Now let's think about it for a second-- if you were an PhD conducting a study and eventually want a great career and to become a professor, what kind of data are you hoping to find if you research this topic? People are so incredibly sensitive about this issue that if you try to publish anything offensive you will immedietly be attacked. Never mind this stuff actually matters when trying to make public policy, if you say anything other than "all races are genetically identical and everyone farts sunshine and butterflies" you will be attacked. If you were a publisher, what kind of articles do you want to publish? One that says "Hey, studies show that certain races might be over-represented in medical school largely because they are smarter. It has less to do with social inequality than most people think, and instead there just aren't many smart *insert racial group here* students able to compete with the many smart *insert ractial group here* studnets"" Can you imagine how crazy people would go with such conclusions? Or, imagine and article which says "All racial groups are basically identical, and any differences we see are due to differences in socioeconomic status." Which is going to get published? Which will help you advance your career, get tenure, and get more funding?
In other words, data from published studies is usually so incredibly biased in some areas it's borderline useless. I have a lot of faith in researchers to answer questions like "What is the specific heat of liquid mercury in standard temperature and atmosphere?" That can easily be tested for in a controlled environment, the data easily reproduced, and no one really has much of an incentive to lie about it. If the specific heat is slightly different from what molecular orbital theory predicted, who cares? This happens all the time and it doens't mean molecular orbital theories are wrong.
I have very, very little faith in research to answer questions such as "How harmful is fast food?" and "Is race and intelligence linked?" For these questions I think you need to apply a lot more common sense and use a lot more general theory. I've been changing my diet and lifestyle a lot in the last few months, and I'm just noticing how often I'm saying "yeah, but I'm going to just use common sense and think about things in terms of the theory of evolution." I've since gone Paleo and am asking myself "in the context of evolution, does it make sense to think I should eat this or do this?" and it seems to be working out so far.
Theory interest me a lot because I feel like you can easily break it down and assign probabilities. There also aren't experiments or studies which are needed to conduct, so you aren't getting a massive amount of filtration for what is actually ever published. I'm going to be posting my thoughts on some issues in the next few months and really want to challenge myself and anyone who reads this to think "Does this make sense? What is the data saying, and how much can we trust the data? Does it agree with other generally established theories we know of (such as diet in the context of evolution)." I pretty much love theory in general and I think we can use it to solve problems way beyond poker, I just think people just aren't stopping and actually thinking enough right now.