Thoughts on small cogs (8)
I believe the answer is:
opinions
'thoughts' is the definition.
('opinion' can be a synonym of 'thought')
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for opinions that I've seen before include "Personal views" , "Points of view, judgments" , "Personal beliefs or judgments" , "Macbeth bought golden ones" , "Viewpoints" .)