Eric B. 's Key Ideas from Atomic Habits
by James Clear

A craving is created when meaning is assigned to a cue. Being aware of cues that trigger cravings can be beneficial for both creating and breaking habits. Optimize your environment by including things that prompt you to complete a desired behavior and removing things that cause you to do undesired behaviors.

Happiness is the state you enter when you no longer want to change your state. It is the space between the fulfillment of a desire and the formation of a new desire. Alternatively, suffering is the space between craving a change in state and getting it.

If your motivation and desire to complete a behavior are large enough, action will ensue regardless of difficulty. 

Behavior is completed through action. Being smart has its advantages, but does not provide motivation that leads to action. Having a healthy degree of curiosity and a hunger for seeking new information will create a mindset with a higher probability for action.

A response is triggered by cravings and cues, inducing feelings of desire to complete actions. At some level, every decision is driven by emotion, and only once this is understood can we begin to think rationally or logically. Clear claims the primary mode of the brain is to feel with the secondary mode being to think. Each of these modes has their respective responses. The feeling mode is associated with quick and nonconscious responses. Oppositely, the thinking mode is associated with slow and conscious responses. 

The source of all suffering is the desire for a change in state. This desire for a change in state is what powers someone to take action. This desire for change can be seen as a craving, with it we are dissatisfied but driven, without it we are satisfied but lack ambition.

The gap between craving and reward determines how satisfied we feel after taking action. The outcome of an action determines our likelihood to repeat a behavior in the future. Outcomes that meet our expectation will increase the likelihood of repeated behavior and those that don't meet our expectation will decrease the likelihood.

Wanting and liking are the the drivers of our behaviors. Without desire and interest, there is no reason to take action. However, there must be a degree of enjoyment in order to continue taking action. Put another way: Feeling motivated gets you to act. Feeling successful gets you to repeat.