Why it exists

Self-help advice about health, learning and family is usually a list of slogans. This page compresses it into one honest mental model: a human life is four overlapping curves — body (peaks ~30, but your habits can shift the peak a decade and halve the decline), mind (processing speed falls, judgment and pattern recognition rise — a transformation, not a decline), heart (wisdom, compassion, gratitude only rise, crossing body around 50), and legacy (what accumulates and never leaves). The insight is simple and uncomfortable: no single curve tells the story — a fulfilling life is about which curves you choose to invest in.

Main features

• Four curves, four quotes — Jim Rohn's body, Henry Ford's mind, Goethe's heart, Barbara Johnson's legacy — each backed by real research directions (the Royal Society's "life begins at 40" work for the body curve).
• Interactive sliders — "Explore Your Curves" section lets you adjust investment in body/mind/heart/legacy and see the trajectories respond; the "sum of your life" curve re-renders live.
• Bronnie Ware's closer — built around the observation that in the final weeks "it all comes down to love and relationships"; the page is a five-minute argument for earlier investment in the curves that don't peak.
• Zero-friction web — one static page, no sign-up, no analytics circus, no JavaScript framework drama; loads instantly, reads like a poem.

Who it's for

• Anyone at a birthday that ends in a zero, deciding where the next decade's effort should go.
• People optimizing only the body curve (or only the career) who need a two-minute visual gut-check.
• Fans of Wait But Why-style essays and anyone collecting honest pages of the small web that Kagi's Small Web celebrates.

How it compares

• Wait But Why's "Tail End" — the classic charts-of-your-life essay; Curves is the interactive, shorter cousin focused on the shape of decline and growth.
• WHO life tables / Gompertz charts — the data behind the body curve, without the human framing.
• Memento mori calendars (Your Life in Weeks) — the better-known life-visualization genre; Curves differs by modelling four lives within one.
• Blogs about longevity — mostly selling something; this page sells nothing and has one slider per curve.

Notes

• It's a personal essay, not a medical tool — the curve shapes are illustrative; the cited Royal Society work is the closest thing to sourcing.
• Written by Vladimir Prelovac, who founded Kagi — the same taste for small, fast, humane software shows.
• The page is view-source friendly: four curves, some SVG, no tracking — a nice reference for how little a single-file interactive essay needs.
• Five minutes to read, considerably harder to put down.

Useful links

• The page: https://vladimir.prelovac.com/curves.html
• Author's site: https://vladimir.prelovac.com/
• "Life begins at 40" — The Royal Society: https://royalsociety.org/news/2015/life-begins-at-40/
• Bronnie Ware, The Top Five Regrets of the Dying: https://bronnieware.com/blog/regrets-of-the-dying/