We have to have knowledge of the history of magic and what has been done before.
1	We	we	PRON	PRP	Case=Nom|Number=Plur|Person=1|PronType=Prs	2	nsubj	2:nsubj|4:nsubj:xsubj	Discourse=explanation-justify:43->39:3|Entity=(4-person-acc:com-cf2-1-ana)
2	have	have	VERB	VBP	Mood=Ind|Number=Plur|Person=1|Tense=Pres|VerbForm=Fin	0	root	0:root	_
3	to	to	PART	TO	_	4	mark	4:mark	_
4	have	have	VERB	VB	VerbForm=Inf	2	xcomp	2:xcomp	_
5	knowledge	knowledge	NOUN	NN	Number=Sing	4	obj	4:obj	Entity=(50-abstract-new-cf3-1-sgl
6	of	of	ADP	IN	_	8	case	8:case	_
7	the	the	DET	DT	Definite=Def|PronType=Art	8	det	8:det	Entity=(51-abstract-new-cf4-2-sgl
8	history	history	NOUN	NN	Number=Sing	5	nmod	5:nmod:of	_
9	of	of	ADP	IN	_	10	case	10:case	_
10	magic	magic	ADJ	JJ	Degree=Pos	8	nmod	8:nmod:of	Entity=(8-abstract-giv:act-cf1*-1-coref-Magic_%28illusion%29)51)50)
11	and	and	CCONJ	CC	_	12	cc	12:cc	_
12	what	what	PRON	WP	PronType=Rel	8	conj	5:nmod:of|8:conj:and	Entity=(52-event-new-cf5-1-sgl
13	has	have	AUX	VBZ	Mood=Ind|Number=Sing|Person=3|Tense=Pres|VerbForm=Fin	15	aux	15:aux	_
14	been	be	AUX	VBN	Tense=Past|VerbForm=Part	15	aux:pass	15:aux:pass	_
15	done	do	VERB	VBN	Tense=Past|VerbForm=Part|Voice=Pass	12	acl:relcl	12:acl:relcl	_
16	before	before	ADV	RB	Degree=Pos	15	advmod	15:advmod	Entity=52)|SpaceAfter=No
17	.	.	PUNCT	.	_	2	punct	2:punct	_
