It’s important to remember that Holmes wasn’t
born Holmes.
Holmes was born like you and me but probably
with greater potential for certain elements
of observation, but he learned over time to
think like Sherlock Holmes.
At the beginning, he probably thought more
like Watson because that’s more of our natural
state.
He’s able to attain what he does because
he’s become an expert of sorts at observing.
He’s become an expert at person perception.
What I mean by this is he has thousands and
thousands of hours of practice, and that practice
has been interwoven with feedback.
So I look at you and I tell you something
about yourself. 
And you say, “No, that’s actually wrong.
That has nothing to do with me at all.”
Or you say, “Wow.
How did you know that?”
So I’m learning which details matter, which
details don’t matter, which observations
are logical, which ones are false.
And over time I build up that expertise that
will allow me to look at you and in one second
say, “Hey, Watson, I think you’ve been
in Afghanistan.”
And it seems like it’s completely just out
of the blue, oh, my God, how did he know that?
But then if you go back, you’ll see that
this is not intuition in the sense of just
“I knew it.”
It’s intuition in the sense of expertise,
in the sense of judgment that has been honed
over years and years of practice.
So, for Holmes, the entire thought process
is akin to a scientist who is doing a research
experiment, so someone who is doing - who
is following the scientific method.
So for him the mind is like an attic, and
what that means is you can store only so much
in it.
The space is finite.
And what you store and how you store it is
incredibly important as you try to figure
out, how do I optimize my mental resources?
How do I then take the things I’ve stored
and access them?
How do I organize them so that there are connections
between them so that I can use them and make
them as part of kind of a broader whole so
I can see the bigger picture and not just
these random components that I put there?
So, what a researcher would do at the beginning
of an experiment is to say, what is my question?
And that’s exactly what Holmes does.
He says, what is my goal?
What do I want to accomplish?
Before he ever opens a case, before he ever
meets a client, he already wants to know what
is it that I want to get from this meeting.
And so he comes into the meeting with a prepared
mindset.
His attic has already been primed, so to speak,
to take in certain inputs and to not allow
other inputs in.
This is important because attention is incredibly
finite, and so we don’t have just endless
resources, so we can’t pay attention to
everything; we do need to be selective to
what we pay attention to.
Now the scientist after kind of setting this
hypothesis would say, okay, how would I go
about testing it?
That’s, once again, exactly what Sherlock
Holmes does. 
After he sets his goals, he goes about observing
and collecting data, and asking, okay, how
do I answer this question?
And what is it about this conversation, about
this person, about this situation, whatever
it happens to be, that will enable me to gather
the data that I will then be able to use to
see whether my hypothesis holds up?
And then he does this thing that every great
scientist does and I think mediocre scientists
probably do not, which is take a step back
and learn to look at the data, recombine it,
look at different possibilities, be imaginative
with that data to see, is there anything that
I didn’t think of beforehand?
Is my mind still open?
Do I still know what’s going on?
Does this data somehow make me think of new
ideas, think of new approaches, think of things
that I hadn’t thought of in the past?
And so he has this incredible space for imagination,
and I think that that is an essential part
of the scientific method as well.
You know, scientists from Feynman to Einstein
have really valued the importance of imagination
and have spoken a lot about it.
So the reason I’m stressing this is because
people tend to forget it when they think about
the scientific method.
Now finally, what you do after that is you
go back to the data and you look at the - kind
of what you’ve done with it and you see
what makes sense based on my observations.
Have I framed the question properly?
Have I accomplished my goal or do I need to
start over?
Because it’s an iterative process.
You may need to go through this method over
and over and over until you finally come to
a conclusion.
And that's kind of the final step of Holmes’
approach.
He always keeps his education going.
He realizes that the scientific method doesn’t
have an end. 
You’re always going to have to go back the
beginning.
It’s going to be a constant feedback loop.
