Early socialists had a habit of describing their "perfect society", down to miniscule detail of how people would live their lives on a day to day basis. This society, of course, was the product of their heads, and prioritized imagination over reality. This is what makes it 'utopian', being impossible from inception. Later, 'scientific socialism' would be coined by Marx and Engels to describe their process of attempting to improve society through critical analysis of existing structures and social modes

Luckily a guy wrote about this.

In essence, Utopian Socialism was the proto-ideology of a broad category of (often Christian) groups from the late 18th to mid 19th century who wanted to create a moneyless, classless society but didn't have a scientific understanding of capitalism or any practical theory of how to bring their goals about.

In modern context it could be summarized as a vision of socialism where the maximum results can be achieved with the minimum amount of struggle/violence, it's important to note though that utopian socialism in essence does not exist as a self described ideology or position, it has always been a perjorative towards idealism.

The big thing that separates utopian from scientific socialism for me is that the utopian tries to abolish contradiction as an idea while scientific socialism analyses and resolves specific contradictions but understands that they're inherent to any kind of relationship. Marxists chase the least-wrong solution through experimentally attacking existing dialectics rather than trying to create the perfect one out of simple agreement.

Star Trek

Everyone gets to become a painter and poet and society still functions

I guess this is an example of a contemporary utopian socialist. https://www.currentaffairs.org/2017/05/imagining-the-end

It’s like you want to build a plane that flies but don’t understand the fundamental principles of physics to guide you. Sounds like a cool idea, but good luck with that.

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