# If rationality skills were Harry Potter spells...

post by lifelonglearner · 2018-03-09T15:36:11.130Z · score: 67 (18 votes) · LW · GW · 9 comments

Want more? Brainstorm more spells in the comments and I'll (likely) do more of these!

comment by Benito · 2018-03-09T16:46:40.293Z · score: 29 (6 votes) · LW · GW

I love this. FYI the minimal change that makes the image of the Empirio spell valid is to write P(B) = P(B|A) x P(A).

comment by loriphos · 2018-03-28T03:05:42.484Z · score: 1 (1 votes) · LW · GW

I realize I'm a couple weeks behind and nobody might read this, but this is false (e.g., if I flip two fair + independent coins and A = "first coin is heads" and B = "second coin is heads", P(B) = 1/2, but P(B|A) x P(A) = (1/2)x(1/2) = 1/4). I think what you mean is P(A and B) = P(B|A) x P(A).

(unless I'm missing some context and we are assuming B is a subset of A, but if so I'm not sure why we are assuming that)

comment by Elo · 2018-03-28T03:22:58.283Z · score: 4 (1 votes) · LW · GW

comment by alkjash · 2018-03-09T18:13:16.532Z · score: 19 (4 votes) · LW · GW

Any chance you'd like to do some cover/chapter art for Murphy's Quest?

comment by lifelonglearner · 2018-03-09T20:45:50.870Z · score: 19 (4 votes) · LW · GW

Sure! I just read it today, and I quite liked it! I'm a little unsure about timelines, but PM on Messenger and we can figure something out?

comment by romeostevensit · 2018-03-09T18:00:00.893Z · score: 18 (4 votes) · LW · GW

These are great and I like the naming.

Genre savviness.

Deliberate practice.

Scope sensitivity/napkinmath/shut up and multiply.

Checklists!

Something around an argument that proves too much, but this could be massaged into a more atomic concept maybe. (falsifiability? rent collection?)

A dispell for isolated demands for rigor.

and of course: Summon Sapience!

comment by Charlie Steiner · 2018-03-10T05:32:16.759Z · score: 8 (2 votes) · LW · GW

A spell for changing your own mind to reflect the world. Maybe "locus alba" or "ire foras"?

comment by fuserofworlds · 2018-03-09T19:41:34.596Z · score: 1 (1 votes) · LW · GW

Now I'm curious about Dark Side Epistemology spells...

comment by romeostevensit · 2018-03-09T22:35:19.024Z · score: 20 (5 votes) · LW · GW

Movus Goalpostia!