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Senses and Instrumentation

Lesson 2.1

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Agenda

Learning Goals
Instrumentation Activities
Reminder

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Learning Goals

After this lesson, you should

Place appropriate trust in instruments where direct observation is not possible (or is less precise/accurate).
Understand that interaction with reality through instruments can extend the belief of a shared objective reality to objects and phenomena to which our raw senses do not have direct access.
Understand the challenges of validating an instrument and general methods of validation.

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Learning Goals: Definitions

Validation Challenges

When there is no objective gold standard (e.g. passage of time, what fluid to use in a thermometer).
When direct observation is messy or impossible (e.g. radio waves, mass of a mountain).

Validation Techniques

Comparison of multiple instruments (e.g. thermometers)
Comparison to direct observation (e.g. naked sight compared to sight with a magnifying glass)
Interactive Exploration: Testing an instrument by changing the thing it is measuring in ways you know through other means, and seeing if the instrument recognizes the changes appropriately (e.g. does hitting the gas pedal increase a car's odometer; see how singing higher and lower notes affects a sound spectrograph; sprayable electrons in Hacking reading).

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Agenda

Learning Goals
Instrumentation Activities!
Reminder

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Instrumentation Activities!

Grab a worksheet and download a spectrograph app if you haven’t already:

iOS

Android

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Instrumentation Activities: Discussion

In all the instruments we’ve looked at, we’ve directly compared them with our senses. How do we check our senses when we are unsure of them? How do we do that for our instruments?

Our senses can be validated just like any other instrument. Since the things we see, hear, smell, touch, and taste allow us to navigate through the world, for which those senses are our only direct input, and they tend to line up with each other, they have some stability and reliability. And, as with testing instruments against each other, we can compare our senses with the observations of others (shared reality!). Since they tend to fit with the reports of others, for the most part, that is our shared reality, such as it is. (Whatever else we might mean by 'reality,' it's hard to say it's not all the stuff that seems to have similar effects on us and everyone else we talk to and observe.)

Furthermore, no instrument needs to be 100% accurate to tell us something about the world. As long as there is some regime in which some of our senses work, we can use that as a basis to start validating other tools and exploring some aspect of the world.

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Instrumentation Activities: Discussion

How can we observe a thing that we can never perceive directly with our senses?

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Instrumentation Activities: Discussion

Not all instruments are as directly interactive as the ones we’ve used here. Describe an entity which you believe exists for which you only have very indirect evidence.

Why do you believe it exists?
Is there anything that might convince you it did not exist?
Is there anything that might convince you that although something like it does exist, it has quite different properties than you had thought?

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Agenda

Learning Goals
Instrumentation Activities
Reminder

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Reminder

Please read the article Why FiveThirtyEight Gave Trump A Better Chance Than Almost Anyone Else for next class!

Link is posted in the syllabus.