VERDICT: TRUE The claim's verifiable assertions — that Hermann Ebbinghaus (a 19th-century psychologist) developed the idea of the "forgetting curve," and that durable learning depends on repeatedly fighting forgetting rather than on first exposure — are all supported by primary sources. The only non-factual elements are subjective framing ("probably more important" than the learning curve, and the poetic definition of learning), which is opinion, not error. **Claim-linked finding 1 — Ebbinghaus's forgetting curve is real, 19th century, and quantifiable.** In the 1885/1913 full text of Ebbinghaus's own monograph hosted by York University, Chapter VII ("Retention and Obliviscence as a Function of the Time") reports his 1879–80 experiments (163 double tests on 13-syllable lists, relearned after intervals from ⅓ hour to 31 days) and states the curve's shape: "One hour after the end of the learning, the forgetting had already progressed so far that one half the amount of the original work had to be expended before the series could be reproduced again… After 24 hours about one third was always remembered; after 6 days about one fourth, and after a whole month fully one fifth of the first work persisted." The monograph itself is dated 1885 — squarely 19th century — confirming the "19th-century Hermann Ebbinghaus" attribution. (https://psychclassics.yorku.ca/Ebbinghaus/memory7.htm — opened) **Claim-linked finding 2 — the forgetting curve was independently replicated in peer-reviewed research.** Murre & Dros (2015), in PLOS ONE, describe "Ebbinghaus' classic experiment on forgetting from 1880 and 1885," call him "the first to carry out a series of rigorous experiments on the shape of forgetting, which he completed in 1880," and report their own successful replication of the curve using the same savings method over intervals from 20 minutes to 31 days — showing that learned material is lost to time unless actively maintained. (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0120644 — opened) **Claim-linked finding 3 — the "battle against forgetting" framing matches Ebbinghaus's own data.** In Chapter VIII of the same 1885 monograph ("Retention as a Function of Repeated Learning"), Ebbinghaus demonstrated that re-learning is the weapon against the curve: series "which have been learned twice fade away much more slowly than those which have been learned but once," and repeated relearning makes them "deeply engraved and fade out less easily." This is the empirical basis of the TikTok's advice that improvement comes from re-engaging material across time, not from the first read-through. (https://psychclassics.yorku.ca/Ebbinghaus/memory8.htm — opened; chapter index at https://psychclassics.yorku.ca/Ebbinghaus/index.htm) **Primary sources cited (independent; university + peer-reviewed journal domains):** - Ebbinghaus, H. (1885/1913), *Memory: A Contribution to Experimental Psychology*, Classics in the History of Psychology, York University: https://psychclassics.yorku.ca/Ebbinghaus/memory7.htm and https://psychclassics.yorku.ca/Ebbinghaus/memory8.htm - Murre, J.M.J. & Dros, J. (2015), "Replication and Analysis of Ebbinghaus' Forgetting Curve," *PLOS ONE* 10(7): e0120644: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0120644 **One caveat:** the poetic opening ("learning is the constant battle against forgetfulness… the mind's need to erase things") is the creator's paraphrase, not a literal quotation from Ebbinghaus, and no opened source claims Ebbinghaus ever defined learning that way. The underlying science, however, is accurate: first exposure alone doesn't cement knowledge, retention decays on a steep curve unless material is re-learned/reviewed, and relearning is faster precisely because traces persist — the "savings" Ebbinghaus measured. Also note I could not open the Library of Congress record or PubMed/Science copies of later retrieval-practice studies (bot-blocked/cookie-gated), but they were not needed, as the two sources above independently establish every factual element of the claim.