What are "bubbles" (echo chambers / filter bubbles), and why are they a hazard for reasoning?

Content is tailored to your existing interests, knowledge and preferences, so you're increasingly served only views you already hold — a "random elimination" of the perspectives that might challenge you.

In a bubble, algorithms adapt what you see to what you already like. The effects compound:

• Marginalised voices vanish and the dominant narrative wins by default, simply because dissenting views are filtered out.
• Ideological narratives get reinforced, whereas sound knowledge should be transmitted in a way that is scientifically grounded, critical and multi-perspectival.
• Self-reinforcing information cascades — driven by bots and algorithms — inflate "attention bubbles," where a topic feels important mainly because everyone is talking about it.

A structural point Budelacci stresses: the platforms doing this filtering (Twitter/X, Facebook, Instagram, TikTok) are not democratically legitimated institutions — they are corporations whose goal is profit and maximising engagement, not informing citizens. The bubble isn't a bug; it serves their business model.