LEEUWENHOEK THE MAN i3 
Our Leeuwenhoek was manifestly a man of great and 
singular candour, honesty, and sincerity. He was religiously 
plain and straightforward in all he did, and therefore sometimes 
almost immodestly frank in describing his observations. It 
never occurred to him that Truth could appear indecent. 
His letters, accordingly, are full of outspoken thoughts which 
more “scientific ” writers would hesitate to put on paper: and 
to the modern reader this is, indeed, one of his particular 
charms—for he is far more childlike and innocent and 
“modern” than any present-day writer. In his own similar 
language he must often have said the beautiful prayer of 
Thomas More: “‘ Our Lorde kepe me continuallye true faithfull 
and playne, to the contrarye whereof I beseche hym hartelye 
never to suffer me live.’’* 
But Leeuwenhoek—like all honest workmen—took a pride 
in his work. He jealously guarded what he believed to be 
true, though always willing to change his opinions when 
cogent arguments were advanced against them. All studious 
readers of his letters will be able to call to mind a score or 
more of places where he confesses his scientific faith. It is 
impossible to quote all these passages here, but a few extracts— 
taken at random—will illustrate this aspect of his personality. 
Writing to the Royal Society in 1692 he says’: 
I well know, Most Noble Sirs, that the propositions I 
come to make, and which I’ve sent you from time to time, 
do not all agree with one another, but contradictions are 
to be found among them: so I will only say once more 
that ‘tis my habit to hold fast to my notions only until 
I’m better informed, or till my observations make me go 
over to others: and I’ll never be ashamed thus to chop 
and change. 
ee ee 
™ Tn one of Sir Thomas More’s letters written in prison to his daughter 
Margaret. See More’s Utopia ete., ed. Sampson (1910) p.281. More was 
born in 1478 and beheaded on 6 July 1535. His Utopia was first published 
at Louvain in 1516. It is unlikely that L. had ever read it, though the 
first Dutch translation appeared in 1653. 
2 Letter 74, 12 August 1692. MS.Roy.Soc. Cf. Brieven, Derde Vervolg, 
p- 507. Not published in Phil. Trans. 
