Trying to understand elasticsearch's schema and types

elasticsearch.sh

$ curl -XPOST http://localhost:9200/myindex/mytype -d '{"foo": ["bar"]}'
{"ok":true,"_index":"myindex","_type":"mytype","_id":"YYfPUL3TQLaL17zhXQ-ELw","_version":1}

$ curl -XPOST http://localhost:9200/myindex/mytype -d '{"foo": [{"foo": "bar"}]}'
{"error":"MapperParsingException[Failed to parse [foo]]; nested: ElasticSearchIllegalArgumentException[unknown property [foo]]; ","status":400}

$ curl -XDELETE http://localhost:9200/myindex/mytype
{"ok":true}

$ curl -XPOST http://localhost:9200/myindex/mytype -d '{"foo": [{"foo": "bar"}]}'
{"ok":true,"_index":"myindex","_type":"mytype","_id":"6Sv7aaBXTu2jH_wYXR4SYg","_version":1}

$ curl -XPOST http://localhost:9200/myindex/mytype -d '{"foo": ["bar"]}'
{"error":"MapperParsingException[object mapping [foo] trying to serialize a value with no field associated with it, current value [bar]]","status":400}

# Why are a list ["foo"] and a list of objects [{"foo": "bar"}] incompatible?
# How should I rearrange my data for storage in an elasticsearch document?

@karmi You're right. I think I thought they should be compatible because I misunderstood elasticsearch's definition of 'schemaless'.