TRUE.
```
$x = [head yes exists in theory "1"] , [head yes exists in theory "3"] , [head yes exists in theory ":-"] , [head yes exists in theory ":- test"] , [head yes exists in theory "AisBisC"] , [head yes exists in theory "DadJoke001"] , [head yes exists in theory "DadJoke002"] , [head yes exists in theory "DadJoke003"] , [head yes exists in theory "HK"] , [head yes exists in theory "IndexOfSentence"] , [head yes exists in theory "Lasagna AI 1"] , [head yes exists in theory "OneToTen"] , [head yes exists in theory "PennyNickel"] , [head yes exists in theory "YisX"] , [head yes exists in theory "addition"] , [head yes exists in theory "and"] , [head yes exists in theory "and 3"] , [head yes exists in theory "and 4"] , [head yes exists in theory "asdf"] , [head yes exists in theory "bgrgndzmul"] , [head yes exists in theory "bit-bits"] , [head yes exists in theory "blue"] , [head yes exists in theory "brackets"] , [head yes exists in theory "bus"] , [head yes exists in theory "calc"] , [head yes exists in theory "car"] , [head yes exists in theory "computer/human"] , [head yes exists in theory "crap"] , [head yes exists in theory "cut test"] , [head yes exists in theory "dad"] , [head yes exists in theory "dang"] , [head yes exists in theory "division"] , [head yes exists in theory "double tasty test"] , [head yes exists in theory "eq"] , [head yes exists in theory "eq test"] , [head yes exists in theory "eq test 2"] , [head yes exists in theory "eval test squaring"] , [head yes exists in theory "first sentence"] , [head yes exists in theory "foot-feet"] , [head yes exists in theory "forall_impl"] , [head yes exists in theory "forceEval"] , [head yes exists in theory "good morning"] , [head yes exists in theory "greatest"] , [head yes exists in theory "guns"] , [head yes exists in theory "human/computer"] , [head yes exists in theory "ice cream"] , [head yes exists in theory "if-user-says"] , [head yes exists in theory "in list"] , [head yes exists in theory "inch-inches"] , [head yes exists in theory "is a theory"] , [head yes exists in theory "is a, has a"] , [head yes exists in theory "is a, has a (NL)"] , [head yes exists in theory "is in list"] , [head yes exists in theory "is-is-not"] , [head yes exists in theory "isLeaf"] , [head yes exists in theory "iter"] , [head yes exists in theory "lasagna"] , [head yes exists in theory "lenny"] , [head yes exists in theory "list comp"] , [head yes exists in theory "list fillers"] , [head yes exists in theory "lolol"] , [head yes exists in theory "mark"] , [head yes exists in theory "mrshutco"] , [head yes exists in theory "multiplication"] , [head yes exists in theory "next"] , [head yes exists in theory "not"] , [head yes exists in theory "not test 1"] , [head yes exists in theory "not test 2"] , [head yes exists in theory "not v1"] , [head yes exists in theory "number of theories"] , [head yes exists in theory "number of theories 2"] , [head yes exists in theory "onetwo"] , [head yes exists in theory "or"] , [head yes exists in theory "red"] , [head yes exists in theory "simpler syntax test"] , [head yes exists in theory "smartmul"] , [head yes exists in theory "subtraction"] , [head yes exists in theory "tasty list"] , [head yes exists in theory "temp"] , [head yes exists in theory "temp2"] , [head yes exists in theory "temp3"] , [head yes exists in theory "unified"] , [head yes exists in theory "user says what is tasty"] , [head yes exists in theory "usermul"] , [head yes exists in theory "verify 1"] , [head yes exists in theory "verify 2"] , [head yes exists in theory "what is tasty"] , [head yes exists in theory "x random test"] , [head yes exists in theory "xor"] , [head yes exists in theory "yes"] , [head yes exists in theory "yes no"] , [head yes exists in theory "yes-yeah"]
```
[done] 2403 ms