Attendees or participants? Contradiction in Scrum Guide / Sprint Planning?

I learned: attendees are passive, participants are active in a meeting.

Where did you learn this? I'm a native speaker of English, and although I'd interpret being a participant as being active, I wouldn't assume that an attendee is inactive.

For instance, I have attended conferences, and participated in group discussions.

I would agree with Simon that attendees are not always passive. If a person is an active attendee then they are participating. I could attend Sprint Planning and either participate or not.

As a Scrum Master or Product Owner, they may attend the Daily Scrum but not be one of the participants. Only Developers are participants.

thanks a lot.

I suppose that I was mislead by some of the free learning exams that I tried. They suggested this clear distinction between attend and participate.

I just tried and did not find that in scrum.org. Neither in the Scrum Guide (which triggered my question) nor in the Scrum Open exam that I repeated today. Indeed, it is good to know that I should not expect this kind of hairsplitting in the real PSM exam :-)

Obviously, the distinction between attendees and participants is not as clear in the Guide as it is said to be in the exam?

The best advice I can give is to think in terms of the commitments which are important in Scrum. In other words, an attendee might also be a participant if they are fully committed to the matter at hand and equally share accountability for outcomes.

There's that old joke about the chicken asking the pig to help start a restaurant called "Ham & Eggs".  The pig thinks for a moment and declines, pointing out that he would indeed be committed, while the chicken would merely be involved.