It's 'as if' we assume our thoughts 'are' perceptions; without recognizing making the assumption. (That's a 'slippery slope').
"All creatures react to perceptions". (hard-wired to do so for safety and survival). We utilize that fact knowingly or unknowingly. The concomitant images of thoughts are perceived.
Believed images are equivalent to perceptions, in effect. (It behooves us to recognize that).
Think of a thought that disturbs you; then think of a thought that evokes the emotion of 'happy'.
When you recognize the role/effect of thoughts, (like you just did in reacting to your thoughts) you can choose the thoughts, (like you just did), you 'want' to experience instead of by default of not choosing.
How many times a day do your react to UNRECOGNIZED thoughts?
How many times a day do you react to other peoples thoughts; they convey to you?