So, Pollack grabbed an index card from his daughter, wrote several personal finance principles, snapped a photo with his phone and posted it online. The actual index card was 4-by-6 inches (rather ...

The index card was a product of the Enlightenment, conceived by one of its towering figures: Carl Linnaeus, the Swedish botanist, physician, and the father of modern taxonomy.

This article is more than 10 years old. Personal finance is often made way more complicated than it needs to be. But does that mean you can basically fit everything you need to know on an index card?

STEP 6: Flip the index card. On the negative side of the index card, tape the remainder of the aluminum foil strip to the negative wire of the LED bulb.