The name "Small Thought" is already suggesting the centre idea of qigong. That is: whoever wishes to learn qigong, he mustn't be thinking big at all.
Human mind is adventurous. Like a wild horse, it knows no limit in imagination and lusting for more power and possession. However contrary to the common understanding, this kind of lusting mind was not at all the absolute evil, but the basic ingredient in forming "qi".
Opposite to this adventurous mind would be the intention to seek for rest and peace, and solitude. To look inside and be still. However it was not at all the single element in the pathway to seek for "qi".
Like the neutralizing of acidity into alkalinity, resulting in the forming of crystal within the solution. Mind that is adventurous would neutralize into the mind seeking for solitude, hence forming "qi" inside our mortal physical flesh.
"Small Thought" is the tool that enhance this change to happen.