ProfessorOwl_PhD [any]

The reason stuff gets inflamed and sensitive with soap and water is because it’s healing the damage, rather than just destroying everything in the damaged area and hoping it grows back right. Your body will generally do fine if you’re young and healthy, but as you get older it becomes more of a risk.

It’s not guaranteed to do more harm than good, but because it destroys healthy cells too it creates a risk that just doesn’t need to be taken. It’s not more effective at preventing infection than soap and water, and it’s not as effective as medical super glue for stopping bleeding, so there just isn’t a place for it any more.

New answer for the specific context:

You did your best with the 2 year old. Toddlers are difficult because they just make noises and expect you to work out what’s wrong for them. Small snack and something to drink are always good starting points, followed by a distraction (like the nursery rhymes video) to get their attention off what was upsetting them.

With the 5 year old, you escalated by increasing the punishment to 15 minutes, and now your brother-in-law pushed it back down she knows you can be overruled. Talk to your sister and her husband to make sure you’re both clear on what limits your comfortable with and what specific punishments to give for breaching them, in line with what they’d normally give, so you can both be sure you’re giving out punishments they feel are appropriate, so there’s no room for her to get you overruled - if she goes to her dad you should both be confident he will back you up. She’s of an age where she is going to test what rules and limitations really exist, so you need to make sure she’s not getting mixed messages about it. You’ll have an easier time distracting her with something interesting than telling her not to do stuff.

Make sure to use vocabulary they understand, but don’t be condescending with it. They’d rather you speak to them like they’re older than they are than younger.

Don’t be overly restrictive of their freedom, but be clear about the limits and make sure to enforce them. Explain the reasons for the restrictions rather than just telling them they’re not allowed and they’ll generally listen.

Give them small jobs to make them feel more responsible and patient about other things.

Do your best to answer their questions properly instead of dismissing them, even if the only answer you can give is “I don’t know”. They’ll listen to adults that they feel listen to them.

How many people do you think are working in computer graphics? It’s specialised knowledge, exactly the kind of thing that should be taught at university to the people it’s relevent to.

you can explain the solution in natural language pretty easily

It’s not about how you phrase the solution, it’s about needing the solution at all.

We use plenty of simple geometry everyday, sure, but you don’t need to be able to even understand what OP’s example says to engage with the world. Like you don’t need to provide a mathematical proof to put a shelf up properly.

So Don’t we need more education about the 3D space in highschools really?

How often do you think most people need to know the advanced mathmatical properties of 3d space?

Absolutely it is, and it even seems to be hard coded in many non communal species, like the wombats that open their burrows to other animals during Australian wildfires, but empathy isn’t powered by the idea of reciprocation. It’s an inherently selfless feeling that doesn’t consider either direct or indirect benefits for the self, and it doesn’t make sense to say that acting on those selfless feelings, against your self interest, is itself selfish.

It deeply upsets and enrages me

But why? It doesn’t affect you. It isn’t in your self interest to be upset by those things, it just makes you feel bad. Wouldn’t it be more reasonable to say that you are simply able to feel and act selflessly rather than invent a form of self interest that involves caring about other people?

and if everyone does the same, some sort of proper balance will be achieved.

What makes you think that logically follows? Why would it not create competing self-interests that can’t coexist?

Even if you broaden it to acting for indirect reciprocal benefit plenty of people act in ways that don’t have a reciprocal benefit. Just look at the Madleen flotilla, everyone there is putting themselves at personal risk for no personal tangible benefit - the position of self interest would be to stay safely away from the war at home. Look at all the local charities that help vulnerable members of their communities for no personal benefit. Look at people acting against their self interest just within their own families, like supporting elderly parents despite the costs and even though their death would speed their inheritance. There is a huge range of actions that fall outside of both direct and indirect self interest that people take every day.

It doesn’t particularly sound like it’s the alcohol you’re craving if you’re only buying it on sale, but there’s definitely some sort of unhealthy mindset going on there with the compulsive purchasing and consumption. When I was an alcoholic I was drinking 3-4 pints on my nights in because I wouldn’t be able to sleep otherwise, not only buying it if it was on sale.
Completely speculating, it sounds like beer on sale became a significant reward mechanism during your homelessness, and you need to find a new reward to shift that focus over to. Some kind of sweet treat, some kind of game or hobby, something you can reach for instead of the sale beer. You need to convince yourself you are worth more than just sale beer, you’re worth the nice things you’d like to have in your life.