all creatures have indexes which are 00:05:21 physical connections between form and meanings so footprints are physical index of smells our physical index is smoke is a physical index of fire those 00:05:32 are recognized by every living creature icons are intentional and they're non arbitrary their physical resemblances so a painting is an icon a sculpture is an 00:05:45 icon they show the ability to represent something based on physical resemblance not physical connection and then finally the most complicated is a symbol which has a form and a meaning but more than 00:06:00 that I won't go into all the details but symbols are actually fairly complex but the most important thing to remember on a symbol is they arise by convention by culture they don't arise any other way 00:06:13 also duality of patterning that just means that we take meaningless items to make meaningful items so take CA TS I'll go into this Katz and English C means 00:06:25 nothing a means nothing T means nothing s means nothing Katz mean something so the ability to take things that don't mean anything make things that do mean something such as cymbals this is a crucial component 00:06:38 of language and I'm not the one who discovered that that's been known for a while compositionality is the ability to put things together and make larger meanings so the and boy and big and ran can go 00:06:53 together to get the big boy ran so so these are very important parts and there are different kinds of grammars