My sense is that the world of the mind precedes the world of action, and so the latter is typically rooted in the former.
In the Eightfold Path of Buddhism, there is "Right Effort" which roughly corresponds with positive thinking and the thought which precedes action.
https://buddha101.com/p_path.htm
That being said, I think the effort is more the point. I am not sure anybody is having 100% positive thoughts and it's more about how you deal with such thoughts when they arise.
In the Eightfold Path of Buddhism, there is "Right Effort" which roughly corresponds with positive thinking and the thought which precedes action.
https://buddha101.com/p_path.htm
Quote:Right Effort:
Right Effort means cultivating an enthusiasm, a positive attitude in a balanced way. Like the strings of a musical instrument, the amount of effort should not be too tense or too impatient, as well as not too slack or too laid back. Right Effort should produce an attitude of steady and cheerful determination.
In order to produce Right Effort, clear and honest thoughts should be welcomed, and feelings of jealousy and anger left behind. Right Effort equates to positive thinking, followed by focused action.
That being said, I think the effort is more the point. I am not sure anybody is having 100% positive thoughts and it's more about how you deal with such thoughts when they arise.