Loren Petrich
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lpetrich.bsky.social
Loren Petrich
@lpetrich.bsky.social
Pronouns: he/him
I have concluded that humanity is entering a second age of renewable energy.

The first age was all of humanity’s existence until recent centuries.

#RenewableEnergy
December 1, 2025 at 8:00 AM
Having discussed cycles of US domestic history, I turn to cycles of US foreign-policy history.

Cyclical theory (United States history) - Wikipedia
en.wikipedia.org/wiki/Cyclica...

Historian Frank J. Klingberg proposed that the US alternates between extroverted and introverted foreign policies.
November 28, 2025 at 4:31 PM
I confess that I like cyclic theories of history, because that makes humanity's history something more than one annoying thing after another, to paraphrase one historian.

But one has to avoid Procrustean theories and seeing patterns in randomness.
November 27, 2025 at 8:21 PM
Ivermectin.

Supposed miracle cure.

Patients: bony vertebrates from salmon to horses. Nothing on sharks or honeybees.

Targets:
- Arthropods:
- - Mandibulates: flies, lice, fish lice
- - Chelicerates: ticks, mites
- Nematodes
Nothing on flatworms: flukes, tapeworms
October 27, 2025 at 10:28 PM
Someone here (or at Threads?) asked for some entertaining label for right-wingers. I have thought of one.

Birch trees.
October 23, 2025 at 4:00 AM
An oddity of our species is greater attention to women’s appearance than to men’s appearance. Though there is abundant cross-cultural evidence of male vanity.
October 12, 2025 at 12:57 AM
There is an oddity of human biology that I haven’t seen much discussion of. Clothing.

Consider people with Paleolithic-level technology in warm climates, people who lived like the first members of our present species. They wear very little clothing.
October 11, 2025 at 11:56 PM
About education, I think that a good way to teach biology is by doing comparative anatomy.

It’s visually interesting, and it’s a good introduction to some broader principles, like evolutionary biology.
October 11, 2025 at 11:45 PM
Artificial intelligence in education? Especially large language models and similar AI.

Doing students’ schoolwork for them? Very, very bad. Like hiring a ghostwriter.

But there is a use for AI that I think is very, very good. Tutoring.
October 11, 2025 at 10:40 PM
Traditional logic is two-valued, with only two truth values: true and false.

But can one add additional truth values, and one can find mathematically coherent multivalued logics.

I will demonstrate by adding the truth value "maybe": either true or false, evaluated with both values.
July 10, 2025 at 8:01 PM
I remember from my childhood the game WFF 'n PROOF - I never had a chance to play it, but I found its rulebook, and I must concede that I am VERY disappointed.

As part of the game, one assembles proofs of theorems by using operators and variables selected by throwing dice.
July 10, 2025 at 6:59 PM
I'm catching up with Flag Day. I've long liked the patterns in the US flags, and I've even worked out how to generate them.

List of flags of the United States - Wikipedia
en.wikipedia.org/wiki/List_of...

Some of them don't look that great, so I've worked out alternatives for them.
July 5, 2025 at 10:36 PM
Today is July 4, 2025, the 249th anniversary of the signing of the US Declaration of Independence. The leaders of thirteen British North American colonies decided to get together to fight off their colonial masters. It was the first successful decolonization in the history of European colonialism.
July 5, 2025 at 12:02 AM
Continuing with the Solar System's past, my favorite bit of evidence is Milankovitch astronomical cycles, which make climate variations like the coming and going of continental glaciers over the last 2 1/2 million years.
June 24, 2025 at 5:52 PM
Some counterevidence to Immanuel Velikovsky's catastrophe scenario in "Worlds in Collision" is evidence that the Solar System has not had big changes over much of its existence.

The Earth is slowly spinning down and the Moon slowly spiraling away, both in evidence over geological time.
June 24, 2025 at 5:31 PM
Where did I respond to someone about Immanuel Velikovsky?

He was a Russian-American Freudian psychoanalyst who became a catastrophe theorist. Sometimes in the 1940's, he got the idea that the Bible contains the record of huge natural disasters.
June 24, 2025 at 4:25 PM
Macro-linguistics: the Altaic language family: common ancestry (genetic) or exchanged features (areal) or both?

Narrow: Turkic, Mongolic, Tungusic
Broad: with Korean, Japanese

That has been a source of controversy for decades.

But can new methods resolve this issue?
May 19, 2025 at 2:26 PM
Some macro-linguistics work: the closest relative to Indo-European is likely Uralic (Finnish, Hungarian, ...).

"I/me" *me- ~ *minä, *mun
"you (sg)" *te- ~ *tinä, *tun
"that" *to- ~ *to
"who" *kwi/o- ~ *ke/i/u
"name" *Hnomn ~ *nimi
"water" *wodor/n- ~ *weti
"big fish" *(s)kwalos ~ "fish" *kala
May 19, 2025 at 1:44 PM
To see what full-scale censorship of news media might look like, I look at a purported document on Soviet media censorship from ~ 1970.

"Party, State, and Citizen in the Soviet Union", p. 140, ed. Mervyn Matthews

This part is available, or at least formerly available, on Google Books.
April 6, 2025 at 12:41 AM
I've learned that there are lots of variations on vegetarianism, including forms of semi-vegetarianism and flexitarianism.

Pollotarianism - will eat chicken, turkey, duck, and other birds, but not red meats - cow, sheep, goat, pig, horse, camel, ... - mammals
March 26, 2025 at 9:19 PM
en.wikipedia.org/wiki/Cyclica...

There is a similar cycle of foreign policy, one proposed by historian Frank Klingberg, but it is separate from the Schlesinger & related domestic cycles.
November 29, 2024 at 10:51 PM
My thread on history cycles may have been exhausting. So where are we now?

In the Schlesinger cycles, in Gilded Age II, the Reagan or Neoliberal Era. Lots of unsolved social problems & efforts to solve them.

Occupy was a flop. Its members had little success in finding sustainable campsites.
November 29, 2024 at 9:43 PM
en.wikipedia.org/wiki/Cyclica...

Theories of human-history cycles have a well-deserved reputation for being Procrustean, but I think that some cycles are plausible.
Cyclical theory (United States history) - Wikipedia
en.wikipedia.org
November 29, 2024 at 7:30 PM
This Thanksgiving, I feel something to be grateful for.

YouTube now has “Playables”, online games that run in YouTube pages.

There are lots of games there: action games, puzzle games, crosswords, card games, board games, …
November 29, 2024 at 7:18 PM