Arjuna asks Sri Krishna (BG 14.21) to narrate the signs and behaviour of a GunAtita, i.e., one who has transcended three constituents (sattva, rajas, and tamas) of nature. Sri Krishna replies that he neither dislikes illumination (knowledge), activity, and delusion when they appear in the form of objects of experience), nor does he long for them when they disappear.

It is instructive to know the thought pattern of a GunAtita. Extracts from BG Bhasyam published by Sri Ramakrishna Math, Madras are reproduced.
“ Light is the effect of sattva; action of rajas; and delusion of tamas. The sage does not hate these when they spring up: ‘A tAmasic mental state has arisen, so I am deluded; a rAjasic action, essentially painful, has sprung up which drags me down from my real nature. This slip from my real nature as Self is tragic. Likewise, an essentially luminous sAttvic state, including discrimination and promoting pleasure has arisen’. Only he whose vision is defective hates these states; not so the sage who has transcended the constituents. Unlike the sAttvic, the rAjasic and tAmasic man who desires these states when they lapse, the sage does not desire them when they disappear. This is the idea. The sage’s attitude to these states is not obvious to the outsider; rather, being evident only to the Self, the sage alone may perceive his inner marks. An outsider, of course, cannot discern the inwardly felt aversion and attachment.” [italics added]

Extracts from Bhasyam, apparently another edition published by Ramakrishna Math (downloaded) are reproduced.
“ – ‘In me has arisen a perception which is a result of tamas; thereby I have become deluded’; so also, ‘In me has risen (the inclination to) action which is painful and is born of rajas. By that rajas I have been actuated, carried away from my own nature. This is a matter of sorrow to me that there has been a deviation from my own nature’; similarly, ‘The quality of sattva, in the form of illumination that is knowledge, binds me by attributing discrimination to me and making me attached to happiness’—
(by thinking) in these ways one dislikes them because of his being not fully enlightened. The person who has transcended the qualities does not dislike them in this manner. Unlike a person having sattva etc., who longs for the effects of sattva etc. which withdraw themselves after becoming manifest to him, the person who has gone beyond the qualities does not long for them in that way when they disappear. This is the idea.
This is not an indication that can be perceived by others. What then? Since this characteristic is perceivable to oneself, it is merely subjective. For dislike or longing, which is a subjective experience of a person, is not seen by another.” [italics added]

Differences in the above depictions though minor, fine-tune our understanding. I have inferred the following from the above depictions.
1 It is a misconception that a GunAtita remains in a thoughtless state.
2 Thoughts of varied types arise in his mind because of vAsanAs (read prArabdha).
3 He is alert to involuntary thoughts.
4 It is the response to thoughts that differentiates him from others.
5 His response is by way of a (deliberate) thought that he is a witness of the thoughts. It is followed by the next thought:
6 As a witness, he need not like or dislike the thoughts as they would die in due course.
7 The above thought process is effortless.
8 A seeker who is not a GunAtita (fully enlightened) would respond to thoughts in a manner appropriate for spiritual progress.