If psychology is not science, then what are the implications ?
If I scratched my left eye, I had to scratch the right one as well. Scratch one leg; had to scratch the other one, too. You may find it funny, as I do now, but you have no clue how bad and uncontrollable it was. I just couldn't stop it at the time, but solved it after two years or so when I changed my mind set and willed myself to stop it because it is nonsense. It felt strange when I stopped, but I managed to overcome it.
Foot over cracks
Another tic was to always step with my right foot over cracks in the ground. I paid so much attention to it that I could have been hit by a car and never notice. My leg physically hurt if I didn't do that, but by changing my mind about it and seeing it as a stupid behaviour, I eventually forced myself to stop it. (video)
I had tons and tons of tics, from physical, almost involuntary movements, to language tics. But a very strange one was: if I was thinking of a song, I had to finish it in my head before doing anything else. You may find it hard to believe, but I couldn't sleep if I didn't finish singing the song in my head. I got rid of that by changing my mind about it.
Finishing the song
The symmetric touch