What makes a Generator
Human Design decides type from two questions, and a Generator answers them yes and no. Yes, the Sacral is defined: at least one channel from the Sacral to another center is complete in the chart, with both of its gates active at birth or at the Design moment. No, no motor reaches the Throat: there is no unbroken chain of defined channels from the Sacral, the Heart, the Solar Plexus or the Root to the Throat.
A Generator's Throat can still be defined, by a channel from the G center, the Ajna or the Spleen, as long as no motor connects to it. That is the whole difference from the Manifesting Generator, who has the same defined Sacral with a motor wired through to the Throat. The rest of a Generator's chart (which other centers are defined, the profile, the gates) varies as widely as any other type's.
The strategy: to respond
Human Design reads the Sacral as a motor that does not start things by itself; it responds. Life brings things to a Generator: a question, an offer, something seen, heard or asked for. The Sacral answers with a response felt in the gut, often as a sound: an "uh-huh" of yes or an "un-un" of no, or a pull toward or away. The strategy is to notice those responses and follow them rather than decide everything in the head first.
Responding is not waiting passively. Generators can put themselves where there is plenty to respond to, and people around them can help by asking yes-or-no questions, which the Sacral answers most clearly. The tradition treats the strategy as an experiment to try in small daily choices before trusting it with big ones.
Satisfaction and frustration
Each type has a signature, the feeling of living the design, and a not-self theme, the signal that something is off. For Generators they are satisfaction and frustration. Satisfaction is described as the feeling at the end of a day spent on work the Sacral responded to; frustration, as the sign of pushing on with things it never said yes to, or of starting things from the mind that the gut did not answer.
Human Design reads Sacral energy as renewable rather than endless: used fully on the right work during the day and restored by sleep. The advice most teachers give is to use it on what lights it up, and to go to bed when it is spent.
Sacral or emotional authority
A Generator always has one of two inner authorities. With the Solar Plexus open, the authority is the Sacral itself: the response in the moment is the answer. With the Solar Plexus defined, the authority is emotional, because the emotional wave outranks the gut: the Sacral still responds, but the tradition advises waiting for clarity over time before a big decision. The measured split between the two is below, with the centers, channels and definition Generator charts have.
Working it out for yourself
The free Human Design chart calculator shows whether your chart is a Generator's, with the channels that define your Sacral. The guide to the five types compares the Generator with the other four, and the centers guide explains what each defined and open center is read as.