Observing it from the self, observing it as, "That idea which I have observed," is dualistic. But this is not the only kind of observation of an idea that can be made.
Care to elaborate on that further?
With regard to your elaborations regarding thoughts, their arising, the cause of their arising, and "the effort that needs to be undertaken for thoughts to arise", I will comment, based on Third Karmapa, Rangjung Dorje's Treatise on Buddha Nature
(21) Phenomena are exlplained to be
(22) Samsara and Nirvana appearing as duality.
(23) This is named "the ground of the latencies of ignorance."
(24) The movements of mental events-correct and incorrect thoughts-
(25) Are the cause of generation;
In other words, thoughts, in general, whether "correct" or "incorrect," are not wisdom, per se.
I'm going to quote from Khenchen Thrangu Rinpoche's commentary--the book is titled On Buddha Essence
, published by Shambhala in 2006--incidentally, I highly recommend this fairly slim volume, along with all of Rinpoche's publications--on page 34:
"..the nature of thoughts is contrary to the true nature, and therefore we cannot directly realize dharmata. So the subtle aspect of thoughts is the appearance of dualism, which develops and becomes more obvious and stronger. First, there is the mere dualistic appearance; when this becomes stronger, the sensory consciousnesses ...appear."
By contrast, Buddhas do not have thought, and do not make effort.