Heinsius and Grotius had been most intimate in their youth:  the divisions which happened in the Republic destroyed this close union:  Heinsius joined the Contra-Remonstrants, and was Secretary to the Commissioners of the Synod of Dort.  Grotius had reason to complain of him on several occasions:  nevertheless, talking with Cardinal Richelieu about him, Grotius greatly commended his genius and learning.  He gives an account of this conversation to his brother; adding, “In this manner I am wont to revenge myself on those who hate me.”  Cardinal Richelieu, though not prejudiced in favour of Grotius, ranked him however among the three first scholars of the age:  the other two were Claudius Salmasius, and Jerom Bignon.  This famous Advocate-General said of Grotius[714], that he was the most learned man who had appeared in the world since Aristotle.

Foreigners who loved the sciences would not leave France without seeing Grotius.  John Christenius, who was at Paris in 1629, had more satisfaction in seeing him, than in the whole kingdom beside:  he writes thus to John Kirkman, June 20, 1629.  “The pleasure I have had, received considerable addition not only from having seen, but also often conversed with that great and eloquent man who has no fellow, I mean Hugo Grotius; for whom I have the highest esteem, and have been for many years of the same opinion with all who know that he possesses singly what would be sufficient to entitle many to great praise.  He is master of all that is worth knowing in sacred and profane literature.  Besides the Eastern languages, there is no art nor science with which he is not perfectly acquainted:  this appears from his agreeable conversation:  ask him about any thing, he immediately gives you an exact answer, and in such a manner as to excite the admiration of those who hear him.  After talking about the sciences, if you enquire of him what passes in this part of the world, or the other, you will imagine you heard the answer of an oracle who delivers what is most worthy to be known.  His virtue is above all I can say of it, and I want eloquence sufficiently to extol so great a man.”

Sarrau[715], who had been prejudiced against Grotius since his leaving the Protestants, ventures not however to decide whether Salmasius or Grotius excelled in literature; and he hesitates to make the determination, even in a letter written to Salmasius, wherein he appears much dissatisfied with Grotius.  “Whether the first place in literature in this age be due to you or to him, posterity will judge more equitably than this generation.”

On hearing of Grotius’s death, he writes to Salmasius in these terms[716]:  “Hugo Grotius was certainly a great man in name and in fact:  he was the star of our age.  How great a loss has learning sustained!  Whilst books and sciences are held in honour his name will flourish.  For my part, whilst I live I shall glory in my intimacy with him.  You now reign singly (he concludes, addressing himself to Salmasius) I pray God you may reign long.”  He calls him elsewhere[717] the Coryphaeus of learning sacred and prophane.