I'd actually argue against this, to a degree. If you're ignorant, you do not know the full consequences of your actions, and therefore whether they're good or evil. This means that, even for two people who mean well, on average the less educated one will do more evil than the more educated one.
That dude with magic blood that cured thousands of kids with a particular genetic defect. I don't remember his name (sadly), but I'm sure someone else here does.
EDIT: James Harrison. And it was 2.4 million babies.
That is practically the perfect example of a good act which is also an act of harm reduction.
Imagine donating blood as a way of paying forward the blood donations that kept you alive during your own surgery, and then finding out that you're some kinda superman with medicinal blood.
Scientists just trying to make us all smarter.
Doctors helping their patients.
Honestly you could apply this to a lot of people just going through their daily job.
Open source software maintainers.
It's basically a shorthand way to see if someone is good. Not returning a cart is no illegal nor a big inconvenience. Returning the cart brings no reward but is the right thing to do. In the absence of reward or societal pressure to return a carr, only the truly good will.
https://www.nytimes.com/2021/06/08/style/shopping-cart-parking-lot.html
I wouldn't call that doing good. That's the bare minimum for participating in society; those who don't are actually evil.
Strictly speaking, not putting it away means you value yourself above others. You're taking your own convenience over other people's inconvenience. It's a very minor act, but could fit the definition still.
They aren't planting them to reduce skin cancer, though. Every action has some positive and negative aspects; you have to look at the intentions.
I'd say good old fashion politeness like saying good morning, giving someone a (real) compliment, and other small random acts of kindness. You do it because you want to not because you expect something.
The lady at work who brings in a shopping bag full of chocolates and lollies once in a while just to make us stupidly happy and giggly.
I'll hold a door for a body going the other way.
Sometimes, I'll even let a truck merge.
One time I cut someone off in traffic by accident and they ended up behind me in a drive thru so I bought their coffee.
I'm no saint tho. I still fart in elevators.
I once vomited in an elevator. Sorry to whomever had to clean that up. I was sincerely ill and had to get home to bed & toilet asap.
Being nice to my partner. Other people. Inviting them for dinner. Caring for children or neighbors.
Medics and nurses, when the patients aren't terminally ill (harm reduction). Whether they're "good people", and how often they do their jobs right can be debated, but properly caring for the sick is a good thing to do.
If we conceive of ethics as rooted in duty or virtue, rather than outcomes, we can then argue that simply doing your duty or being virtuous are good regardless of whether they lead to harm reduction or mitigation. The people here who have suggested just doing your job well (a duty) or being polite (a virtue) are putting forward a model of ethics based on these ideas.