[wavemode]

You can have a consistent reputation for success without having real magical powers.

Being lucky is an option. ("I shall cause it to rain" and it just so happens to rain.)

Outsmarting your client is another option. ("I shall cause it to rain... tomorrow" - meanwhile, you have used meteorology to predict that it will rain tomorrow.

Lies and rumors are a third option. ("That magician can make it rain! I saw it with my own eyes!" meanwhile it's actually just a baseless rumor which has circulated around town for a while.)

[TrainedMonkey]

Confirmation bias is a thing. If you believe that magical powers are real you will find a way to explain away when it does not work while celebrating loudly when it does. For example if your wizard cannot cause rain it's because the curse is too powerful etc. Additionally growing up with something, such as when everyone around you believes something, makes it somewhat unlikely that you will question it. Finally, if everyone around you believes something there is strong pressure to do the same thing to fit in.

I have a theory that a lot of mental biases could be explained by energy minimization - changing beliefs requires brain reconfiguration which is expensive, so we tend not to do it... unless it's imperative to survival.

[Jensson]

> I have a theory that a lot of mental biases could be explained by energy minimization - changing beliefs requires brain reconfiguration which is expensive, so we tend not to do it... unless it's imperative to survival.

I am pretty sure this is a very variable trait among humans, some change their mind easily others almost never change their mind. Its expensive as you say, probably communities survive best when some change their mind easily and most keep their mind steady and only change when presented overwhelming evidence (usually from the minority that easily change).

[empath75]

People who do that kind of thing for a living are very good at setting low expectations for success and blaming outside forces for failures and taking credit for every lucky hit. Dowsers, cold readers, etc.. it hasn't changed for centuries and con artists and magicians use all the same techniques today.

[bluefirebrand]

> very good at setting low expectations for success and blaming outside forces for failures and taking credit for every lucky hit

Sounds like a lot of management and executives I've ever worked with honestly

[amingilani]

Reminds me of this old con idea. Get a mailing list of 1024 people, send half an email that the market will go up, and half that it will go down.

The next day, half of them will see you got the prediction correct. Of those, send a further half a prediction that it will go up, and the other half that it will go down.

After 7 total rounds you’ll have 16 people that have seen you consistently predict the market for 7 days.

Sell them your next prediction.

[robaato]

Derren Brown has TV shows where he implements this idea. Entertaining.

[interroboink]

This reminds me of the story of Fermi and the "great generals"[1]:

  During the Second World War, the physicist Enrico Fermi asked General
  Leslie Groves how many generals might be called ‘great’, and
  why. Groves replied that any general who won five major battles in a
  row might be called ‘great’, and that about 3 in every 100 would
  qualify. Fermi countered that if opposing forces are roughly equal,
  the odds are 1 in 2 that a general will win one battle, 1 in 4 that he
  will win two battles in a row, 1 in 8 for three battles, 1 in 16 for
  four battles, and 1 in 32 for five battles in a row. ‘So you are
  right, General, about three in a hundred. Mathematical probability,
  not genius’.

[1] quoted from (PDF): https://www.cambridge.org/core/services/aop-cambridge-core/c...