A portrait has been discovered in 1952 at Corpus Christi College, Cambridge, which is most likely of Christopher Marlowe.- The age  and date of the portrait as inscribed in the top-left corner are generally fit to Marlowe, who was born in February 1564, and who attended the College between 1580 to 1587. The latin inscription says "Aged 21 in 1585". The impresa inscribed on the portrait beneath the Dating is:

"Qvod me nvtrit me destrvit" ("that which nourishes me, destroys me") 

 It dates at least back to 1557 and  is of French/Italian origin.
The identical (or very similar) motto  (s.also Blog 259) can be found in Shakespeare's Sonnet 73   or Pericles Q1,  in which  the Prince of Tyre bears the same impresa on his shield for the tournament  (s.Faksimiles)
You also find Marlowe's dialectic  philosophy ("contrarities") in authors such as:
W.C. »Polimanteia« 
»(…) and make me nourish them to my owne destruction (…)«
(…) and to nourish that flame which consumed Greece (…)«
 »(…) and have made me blow it till I burne to ashes (…)«
or  W.B. :
That Which seems best is worst. 1617 [booktitle]
or others such as Barnabe Barnes, Francis Davison, John Davies, Thomas Bastard,  Wiliam Basse a.o.

It is difficult to imagine  that all,  Marlowe, Shakespeare and so many other persons would have used this specific "comple-mentary dialectic philosophy of life",  in the same era and to this diversity. One can borrow certain preferred words and texts, but to take over the  motto or philosophy of life of another  Person  is devoid of logic and would debase  the work  of Shakespeare. These observations support the

-> Marlowe/Shakespeare authorship thesis:

,There was only one towering poetic genius in his time!  Christopher Marlowe.  He was  forced  for various reasons to write - already in his "official life time" - under pseudonames  , and not only under the name of Shake-speare but under many other pseudonyms, which he changed throughout his life such as George Wither.-
It is by no means coincidental, that George Wither in his "Collection of Emblems" used  Marlowes life Motto (s.Faksimiles) .

The only or most plausible explanation is that the author behind  Marlowe's portrait, behind Shake-speare's lines,  behind  Wither's emblems  and behind  the others was always the same.....   

Comparing King Lear Q1/Q2(1608/1619) with the First Folio(FF1623) serious questions arise.- Unfortunately in his books „Contested Will: Who Wrote Shakespeare?“(2011) and in  „The Year of Lear, Shakespeare in 1606 (2015)“  James  Shapiro did not deal with such problems like:
1).Who corrected the text (s.Example Faksimile.- King Lear,  from  
    „mistresse of Heccat“ ( Q2 1619)    to    „miseries of Heccat“ (FF 1623) or
                „shall be“                              to      „shall to my bosome be“   
2.) Who was interested in (and responsible for) many of such crucial text changes between 1619 and 1623?
3.) Why King Lear (and his author)  in Q1/Q2/FF does express that "the barbarous Scythian" [Tamburlaine alias Marlowe] shall be as well neighbour‘d, pittied and releeved as his Daughter [Cordelia]
4.)Why in 1623 the passage of „The barbarous Scythian“  was clarified  by „shall to my bosome be as well neighbor’d, pittied and releev’d as my (some-time) daughter [Cordelia]
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"King Lear" is a gloomy tragedy with a sense of deep general pessismism likely written in 1605.  Consider that Marlowe's legal  father "John Marlowe" died in February 1605 (his mother in July 1605) Robert Ayres and others assume that Marlowe was a bastard.- his biological father Roger Manwood?) 
( s.also pevious Blog 449) What is the reason that Shapiro omitted  deliberately Marlowe in his "Contested Will"?. - His ignorance forced him to ignore  such  great allusions to Marlowe  in King Lear illustrated here . Without -->a plausible theory you will not get any sensible interpretation!