Seneca Quote

[Lucus Eques]

Salvete, amici! Vita me occupat, attamen Latine corde menteque semper vivo.

I found a quote of Seneca's I greatly admire (below), but I cannot for the life of me find the original Latin (at, say, TheLatinLibrary.com); first, I'm not sure if this is Seneca the Elder or Younger, and I haven't found the right word yet (apparently) to search for.

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A single lifetime, even though entirely devoted to the sky, would not be enough for the study of so vast a subject. A time will come when our descendants will be amazed that we did not know things that are so plain to them.

— Seneca, Book 7, first century AD
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Any thoughts?

[Lucus Eques]

Update: I may have found the second sentence here:

http://thelatinlibrary.com/sen/sen.qn7.shtml

[25,5] Veniet tempus quo posteri nostri tam aperta nos nescisse mirentur.

But it's not joined with the first. Strange.

[Lucus Eques]

Update 2 (from the same link above):


[25,4] Veniet tempus quo ista quae nunc latent in lucem dies extrahat et longioris aeui diligentia; ad inquisitionem tantorum aetas una non sufficit, ut tota caelo uacet: quid, quod tam paucos annos inter studia ac uitia non aequa portione diuidimus? Itaque per successiones ista longas explicabuntur.

[25,5] Veniet tempus quo posteri nostri tam aperta nos nescisse mirentur.


It appears to be similar, but pieced together. Thoughts? If find this strange, if it's the right answer.

[Imber Ranae]

Excepting for the missing content in the middle, the English version of the quotation seems pretty faithful to the original:

Ad inquisitionem tantorum aetas una non sufficit, ut tota caelo uacet...Veniet tempus quo posteri nostri tam aperta nos nescisse mirentur.

"A single lifetime is not sufficient for the investigation of so great of things, even though the whole [lifetime] be at leisure for the heavens...A time will come when [in which] our descendants could be amazed that we did not know things so evident [to them]."

[Lucus Eques]

Many thanks! I stuck with that one.