…
„Confirmation bias is powerful and dangerous specifically because it
creates the illusion that the data supports our beliefs, because we are
unaware of the degree to which we have filtered and biased that
information. The internet is a setup for confirmation bias.

The extreme version of this phenomenon is what we call
“echochambers.” Filtering information can be formalized into online
communities where only one perspective is expressed, and information
that supports that perspective is shared, while opposing information is
filtered out or directly contradicted. This is a pervasive effect, and
is true of scientific and skeptical sites as well as pseudoscientific
ones.

Another potential problem is the confusion of knowledge with expertise. This is often what leads to cranks
– people who may be very smart and have a great deal of factual
knowledge, but come to absurd conclusions in which they have high
confidence. One problem with cranks is that they do not properly engage
with the relevant intellectual community.

It is critically important to engage with the community, especially in
highly complex and technical areas of knowledge. It can be very
difficult for any individual to see a complex issue from every angle,
and to consider all perspectives. Left alone we will tend to create a
neat narrative, and become increasingly convinced in the truth of that
narrative. Engaging with the community will tend to challenge that
narrative, leading to a deeper and more nuanced understanding of the
topic. This is the heart of true expertise.

Studying a subject alone by searching online can be a crank factory –
giving factual knowledge without really engaging with the ideas. Then
the echochamber effect can give the illusion of engaging, but only with a
biased community rather than the broader community. The result are
people who falsely believe they have sufficient knowledge in areas they
do not truly understand.“