|The Thinking Man sculpture at Musée Rodin in Paris (Photo credit: Wikipedia)|
What the pharmacist said must have reasons, but by my own experience his words are not sufficient. First of all he didn't mention one of very important reason for heart malfunction: energy overdrawn. I believe fatigue can be the biggest burden to heart, that's why marathon competition is basically a "heart function competition". Second, about "thinking negative", I am not in complete agreement with this popular notion. My own experience tell me that it was not necessarily thinking "negative", but "thinking too much" that damaged my heart or other physical function, no matter thinking "positively" or "negatively". To be more specifically, it is logic type of thinking, problem solving thinking, memorizing, or any other type of LEFT SIDE brain works that overdraw my energy, caused many negative physical consequences. In fact, I enjoy thinking, which means I am happy when I doing such things, but I still got sick because my body simply cannot support my "happiness".
Why? I am not a scientist so I cannot put this in a profession analysis. But put my understanding in plain words, I think the reason is that our left side of brain is like brain muscle, when it works it would cost our body energy. Imagining our bodies would get trouble if we over exercised, same when we over exercised our left brain.
What would be the worst is thinking too much without physical exercise. I found a analogy here: a car motor and battery. Imagining battery is our brain (left brain), car motor is our body (or heart), if the car is being driving, motor is working, battery gets charged; but if we only turn on electric without turning motor on, letting battery working alone, battery dies very soon. So is our body function, if we keep physical exercise, our brains would get "charged", we can think more, and think sharper; but if we don't exercise, our brain function cannot work as well we want. Not only that, a sedentary life style - using too much brain but not body, we get into chronic health problems*.
At least this is how I got mine problems - during all earlier years of my life I exercised very little and thought too much. Now, since my body function is so weak that the damage of thinking has been more and more 'tangible". I found whenever my health was not in good shape, any serious reading or thinking would cause my heart beating irregularly (or any other type of malfunction) almost immediately. On the contrary, "thinking sad", or sadness alone never caused me any discernible physical problems. I remember when my mother died almost two years ago, I was sad, overwhelmingly, for several weeks, but I did not get any relapses, not even minor crashes. Not only that, strangely, shedding massive amount of tear even help me sleep, so my health condition was even more stable.
I understand that there is a difference between "thinking sad" and "feeling sad" - the former is more like a negative thinking, stress or depression, the later is more a emotion release, which is not necessarily a type "thinking".
So my point is simple: it is not necessarily "thinking sad" that make us ill, but thinking itself. Of course I am not against thinking at all, since it is one of my favorite "hobbies". I believe as long as we feel good, keep balance between physical and mental work, certain logic thinking is just like body exercise in gym, is healthy.
*I have a person observation and thought on the strong anti-rationalist tendency existed in Chinese traditional culture. It is a common belief among Chinese people that "thinking" is harmful to physical health, and because of this belief, Chinese culture never encouraged logic reasoning, never developed true science. The reason of this, I believe partially is because of the Chinese people's belief, partially because of the overall health condition of Chinese population. Chinese civilization encouraged a sedentary life style from beginning, and this lifestyle weakened Chinese people's physical condition (I once said that all Chinese medicine is about Chronic fatigue syndrome). I am also more and more convinced that cultural ideology somehow related to the its people's physical condition, i.e., the physically stronger people, such as nomads, tend to be more adventurous, and physically less strong people, such as those agricultural type of people, are more reserved or conservative. While many ancient (and modern) Chinese people are right about the fact that thinking could be harmful to physical health, they failed to realized that physical strength can also enhance mental power.