Habits And Behavior

noun a particular behavior that has become automatic through repetition

• Despite her best efforts, she found herself reaching for her phone out of force of habit.
• I still tie my left shoe before my right out of force of habit.
• I always check my pockets for my keys, it's just force of habit at this point.
• He couldn't help but feel a pang of sadness every time he passed her favorite coffee shop, out of force of habit.

adjective not thinking or using reason; thoughtless

• He acted in an unthinking manner, not considering the consequences of his actions.
• She made an unthinking decision without really thinking it through.
• Don't be so unthinking, dude. Think before you act.
• His unthinking behavior was like a train running off its tracks, causing chaos everywhere.