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What are the key principles of Stoic philosophy?
GPT-5.2
Stoic philosophy centers on four key virtues: wisdom, courage, justice, and temperance. The Stoics believed we should focus only on what we can control.
How can I apply this daily?
GPT-5.2
Start each morning with reflection. When challenges arise, pause and ask: "Is this within my control?"
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Compare quantum and classical computing
Claude Sonnet 4.6
Classical computers use bits (0 or 1). Quantum computers use qubits that can exist in superposition—both states simultaneously...
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Claude Sonnet 4.6 ✓
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Grok 4.2 xAI
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Marcus doesn't watch. It doesn't judge. It doesn't sell. Built on the belief that your thoughts are yours alone — Marcus gives you access to the world's most powerful AI without ever asking who you are.

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GPT-5.2OpenAI
Claude Sonnet 4.6Anthropic
Gemini 3.1 ProGoogle
Grok 4.2xAI
Sonar Reasoning ProPerplexity
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Seedance 2.0ByteDance
GPT-5.2OpenAI
Claude Sonnet 4.6Anthropic
Gemini 3.1 ProGoogle
Grok 4.2xAI
Sonar Reasoning ProPerplexity
DeepSeek R1DeepSeek
Gemma 3Google · On-device
Seedance 2.0ByteDance
"The happiness of your life depends upon the quality of your thoughts."
Marcus Aurelius — Meditations

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Marcus was named after the philosopher-emperor who believed in self-governance and inner freedom. In a world where every AI company monetizes your data, Marcus stands apart. Your prompts are not products. Your creativity is not training data.

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Your thoughts are yours. Your words are yours. Your creativity is yours.   We don't read them. We don't store them. We don't sell them. We don't train on them. Ever.
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